Proto-Siouan language

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The Proto-Siouan language is the reconstructed ancestor of the Siouan languages.{{multiref|{{harvnb|Sutton|2024|pp=328–329}}.|{{harvnb|Collette|Kennedy|2023|p=xvii}}.|{{harvnb|Kaufman|2016|p=40}}.}} The interrelatedness of the language family was first identified in 1836 by Albert Gallatin, a Genevan-American ethnologist and Founding Father, who named it after its most-widely recognized members, the Sioux.{{sfn|Kasak|2016|p=8}}{{sfn|Mirzayan|2023|p=1448}} In 1881, the Swiss-American scholar Albert Gatschet worked on documenting the Catawba language and commented on its similarity to the Siouan languages of the Great Plains of the United States and Canada.{{sfn|Kasak|2016|p=9}} Two years later, Horatio Hale similarly linked the Tutelo language of Virginia to other Great Plains Siouan languages in his 1883 description of the tribe.{{sfn|Kasak|2016|pp=8–9}}

In 1816, the work of the German scholars Johann Adelung and Johann Vater first described the relationship between Catawba and Woccon using primarily a side-by-side word list. Twenty years later, Gallatin built significantly on their work, describing the relationship as phylogenetic and relating these languages to the Siouan family.{{sfn|Kasak|2016|p=8}} Work published by Frank Siebert in 1945 is considered to have definitively proven the relationship.{{sfn|Campbell|1997|p=140}}

Although historians have identified at least twenty-five Siouan-speaking ethnic groups, it is difficult to estimate the number of languages spoken, as dialectal differences and, in some cases, scant attestations make determining the precise number difficult.{{sfn|Mirzayan|2023|p=1448}} The Siouanists David Rood and John E. Koontz estimate that there are between fifteen and eighteen attested Siouan languages.{{sfn|Rood|Koontz|2002|p=259}} Robert L. Rankin puts the number as simply "more than fifteen".{{sfn|Rankin|2004|p=202}}

Proto-Siouan was probably spoken around 3000 BC, splitting off into the Eastern Siouan and Western Siouan languages around four thousand years ago.{{multiref|{{harvnb|Kasak|2016|p=7}}.|{{harvnb|Rankin|1996|p=124}}.|{{harvnb|Miestamo|Bakker|Arppe|2016|p=246}}.|{{harvnb|Campbell|1997|p=142}}.|{{harvnb|Coen|2021|p=14}}.}} Earlier efforts to date the language differed drastically from one another, from the end of Pleistocene to around 800 AD, but archeological records and research into shared vocabulary has yielded a more narrow estimate of around five thousand years ago.{{multiref2|For earlier datings, see {{harvnb|Rankin|2003|p=264}}.|For everything else, see {{harvnb|Rankin|2003|pp=290–291}}.}} Glottochronological dating of the Eastern–Western split has yielded mixed results. Robert Headley estimated that the Eastern and Western Siouan languages split around 1150 BC.{{sfn|Rankin|2003|p=264}} The mathematician Thaddeus C. Grimm employed a methodology developed by the American linguists Morris Swadesh and Robert Lees, and estimated the same split occurred around 2285 BC, though another one of his calculations argued for 5000 BC.{{sfn|Rankin|2003|p=264}} Rankin argued that this split should be dated to roughly 2000 BC.{{sfn|Rankin|2003|p=264}}

Archeological evidence has also supported the 3000 BC dating. The gourd species Cucurbita pepo, for example, has been used as one basis for this estimate; evidence that cucurbits were beginning to be domesticated appears in the archeological records between around 3400 BC to around 2300 BC.{{sfn|Rankin|2003|p=267}} It is well-documented that the Siouan languages share a commonly-derived term for the plant, even across great geographic and phylogenetic distances such as in the case of the Mandan language, formerly spoken in North Dakota, and the Biloxi language, formerly spoken in Mississippi and Louisiana.{{sfn|Rankin|2003|p=267}} The Proto-Siouan term for these cucurbits has been reconstructed as {{lang|sio|*hkó:-re}} and its descendants include Crow {{lang|cro|kakúwi}} ('squash, pumpkin'), Mandan {{lang|mhq|kó:re}} ('squash'), and Osage {{lang|osa|hkohkó ma}} ('cucumber').{{sfn|Rankin|2003|p=268}} Several other terms for plants have helped linguists reconstruct other divisions within the greater Siouan family.{{sfn|Rankin|2003|pp=290–291}}

{{broader|Linguistic homeland}}

File:Ohiorivermap.png (in yellow) is considered a likely {{lang|de|Urheimat}} for Proto-Siouan.]]

Although the modern Siouan languages are spoken in the Great Plains, scholars believe that the language originated in and around the Ohio River Valley.{{sfn|Kasak|2016|p=11}}{{sfn|Kaufman|2018|pp=145–146}} Earlier scholarship, namely the work of the American archeologist James Bennett Griffin, argued that the Siouan homeland was somewhere in the Allegheny Piedmont in modern-day Virginia and North Carolina during first contact with European settlers.{{sfn|Kaufman|2018|p=146}} Siouan-speaking peoples had a wide area of influence in the eastern regions of the modern-day United States. Horatio Hale noticed that several toponyms in the Appalachian region appeared to be of Siouan origin, especially between modern-day Virginia and North Carolina.{{sfn|Kasak|2016|p=9}} Other onomastic data has helped to confirm this view.{{sfn|Kaufman|2018|p=145}} The oral history of the modern Siouan-speaking people also provides some support; John R. Swanton gathered a number of accounts from speakers which indicated a homeland east of the Ohio River and the Hidatsa people indicated similar origins to Washington Matthews.{{sfn|Kaufman|2018|p=146}} A Kaw chieftain recounted to James Owen Dorsey that his people originated in modern-day New York abutting the Atlantic, which they called the "Great Water".{{sfn|Kaufman|2018|p=146}}

It appears that the push westward was the result of wars of conquest over hunting grounds by the Iroquois pushing southward from their own {{lang|de|Urheimat}} in the Finger Lakes region of Western and Central New York.{{multiref2|For the origins of the Iroquois, see {{harvnb|Schillaci|Kopris|Wichmann|Dewar|2017|p=448}}.|For everything else, see {{harvnb|Kasak|2016|pp=10–11}}.}} Successive Iroquois victories caused a massive displacement of Siouan-speaking populations, probably occurring during the 1600s following an increase in European colonization efforts on the American Eastern Seaboard and the start of the Beaver Wars. However, the push was not instantaneous nor universal; the Lakota are attested near modern-day Chicago in 1648, putting estimates of their migration over the Mississippi River sometime around the turn of the 18th century.{{sfn|Kasak|2016|pp=10–11}} Other members of the Siouan family, however, were adopted by the Iroquois; the Tutelo people, for example, were formally adopted in 1753, settling around Cayuga Lake, one of the Finger Lakes, in 1771.{{sfn|Campbell|1997|p=141}} They remained with the Cayuga people during their subsequent migration to Canada following the American Revolution.{{sfn|Campbell|1997|p=141}}

The displaced tribes' migration from the original {{lang|de|Urheimat}} obfuscated the relationship of some of the languages, with some such as Biloxi and Ofo being pushed into, and influenced by, the Lower Mississippi Valley sprachbund.{{sfn|Kaufman|2016|p=39}} The Ofo language, indigenous to modern-day Ohio before being forced out by the Iroquois, was thought for many years to be a member of the Muskogean languages of the Deep South, in part because it contained the {{IPA|/f/}} phoneme which is absent from all other Siouan languages.{{sfn|Kasak|2016|p=9}}{{sfn|Rankin|2015|p=52}} In 1908, Swanton met an Ofo speaker, Rosa Pierrette, living among the Tunica people in Marksville, Louisiana.{{sfn|Rankin|2015|p=52}} His work linked the language to the Dakota language in the Great Plains.{{sfn|Kasak|2016|p=9}}{{sfn|Rankin|2015|p=52}} Similarly, Gatschet's published work on Biloxi, then found in the Gulf Coast regions of modern-day Mississippi and Louisiana, placed it phylogenetically in the Siouan family; his work was later supported by Dorsey's ethnographic work on the tribe in 1893.{{sfn|Kasak|2016|p=9}}

Reconstructions of Proto-Siouan's vowel system indicate five oral vowels and three nasal vowels, each of which had contrastive vowel length.{{sfn|Rankin|Carter|Jones|1998|p=366}}{{sfn|Kasak|2024|pp=30, 76}} The vowels reconstructed for Proto-Siouan are as follows:{{multiref|{{harvnb|Rankin|Carter|Jones|1998|p=366}}.|{{harvnb|Mirzayan|2023|p=1466}}.|{{harvnb|Blevins|Egurtzegi|Ullrich|2020|p=327}}.|{{harvnb|Kasak|2024|p=30}}.}}

It is possible that an earlier form of the language, known as "pre-Proto-Siouan", may have had nasalized forms of {{lang|sio|*e}} and {{lang|sio|*o}}, but these may have been lost as the result of a merger with the oral forms.{{sfn|Kasak|2024|p=77}} Because most Siouan languages mark for vowel length, vowels in Proto-Siouan have been reconstructed as having both long and short forms, though the modern understanding vowel length in the family's extinct members has proven difficult as earlier research did not typically account for length at all.{{sfn|Rankin|Carter|Jones|1998|p=370}} Length in Proto-Siouan was probably somewhat predictable and had different effects on tone in the daughter languages.{{multiref2|For the predictability of vowel length, see {{harvnb|Rankin|Carter|Jones|1998|p=370}}.|For its effect on tone, see {{harvnb|Rankin|Carter|Jones|1998|pp=368–369}}.}}

Nasal vowels are notable in Proto-Siouan in part due to the typologically-rare absence of nasal consonants.{{sfn|Rankin|Carter|Jones|1998|p=370}}{{sfn|Kasak|2024|pp=30, 50}} All examples of nasal consonants in modern Siouan languages are explainable through series resonants followed by nasal vowels; for example, when {{lang|sio|*w}} is followed by a nasal vowel, it may become {{IPA|[m]}}.{{sfn|Rankin|Carter|Jones|1998|p=370}}

The consonants are as follows:{{multiref|{{harvnb|Rankin|Carter|Jones|1998|p=366}}.|{{harvnb|Mirzayan|2023|p=1466}}.|{{harvnb|Blevins|Egurtzegi|Ullrich|2020|p=327}}.|{{harvnb|Kasak|2016|p=16}}.}}

The language contained two consonants known as "funny w" and "funny r", written as {{lang|sio|*W}} and {{lang|sio|*R}}, respectively.{{sfn|Mirzayan|2023|p=1466}} While these consonants are thought to have been similar to {{lang|sio|*w}} and {{lang|sio|*r}}, their reflexes in attested Siouan languages are distinct; while the outcomes of {{lang|sio|*w}} and {{lang|sio|*r}} remained resonants in the descendant languages, {{lang|sio|*W}} and {{lang|sio|*R}} typically develop into obstruents or resonant–stop clusters.{{sfn|Mirzayan|2023|pp=1466–1467}}{{sfn|Blevins|Egurtzegi|Ullrich|2020|p=327}} Evidence suggests that {{lang|sio|*W}} may have been the result of a geminated {{lang|sio|*w}}, typically crossing a morpheme boundary, or more rarely when {{lang|sio|*w}} is abutting a laryngeal consonant.{{sfn|Rankin|Carter|Jones|1998|p=370}} The origin of the {{lang|sio|*R}} phoneme is more opaque, though it may represent a clustering with a laryngeal or some other consonant; {{lang|sio|*r}} tends towards similar reflexes when in clusters such as {{lang|sio|*wr}}, {{lang|sio|*sr}}, and {{lang|sio|*šr}}. Similarly, Mandan evidence supports that a rhotic–glottal stop cluster may have led to this outcome.{{sfn|Rankin|Carter|Jones|1998|p=370}} Linguists have attempted to remove these phonemes from the roster, though without a clear origin they have remained a part of the historical analysis.{{sfn|Campbell|1997|p=142}} More recently, scholars such as Juliette Blevins have argued that the voiced stops {{IPAblink|b}} and {{IPAblink|d}} may be better representations of "funny w" and "funny r", respectively.{{sfn|Blevins|Egurtzegi|Ullrich|2020|p=327}} This analysis argues that the behavior of these sounds in clusters – progressive assimilation causing the voiced consonant to voice the following voiceless one – is more typologically common than the inverse.{{sfn|Blevins|Egurtzegi|Ullrich|2020|p=327}} This theory also helps to explain some of the phonological properties found in Lakota.{{sfn|Blevins|Egurtzegi|Ullrich|2020|pp=327–328}}

Proto-Siouan has also been reconstructed with preaspirated stops. Several Siouan languages either retain a preaspirated series or have a descended set of reflexes; in either case, this set is treated as a single unit in syllabification and segmentation.{{sfn|Rankin|Carter|Jones|1998|p=366}}{{sfn|Mirzayan|2023|p=1467}} The preaspirated series were not originally phonemic, but rather the result of a regular phonological process whereby plain voiceless stops were preaspirated whenever the following vowel is stressed. This process has been termed Carter's law, after {{ill|Richard T. Carter|WD=Q134944588}} who first described the phenomenon in his work on Ofo.{{sfn|Rankin|Carter|Jones|1998|p=366}} This change, however, was later phonemicized and several sets of cognates attest the set as distinct phonemes.{{sfn|Rankin|Carter|Jones|1998|pp=366–367}} Although this series is considered to have been phonemic, several languages – including Hidatsa, Crow, and Mandan – lost this series during their linguistic evolution.{{sfn|Larson|2016|p=66}}{{efn|Strictly speaking, modern Hidatsa does exhibit preaspiration, though it is the result of another process causing {{IPA|/x/}} to lenite to {{IPA|[h]}} before {{IPA|/k/}}.{{multiref|For Hidatsa having preaspirates, see {{harvnb|Mirzayan|2023|p=1466}}.|For the process, see {{harvnb|Larson|2016|p=67}}.}}}} In Ofo, Ho-Chunk, the Dakotan languages, and the Chiwere dialects, the preaspiration became postaspiration, though these were independently motivated and do not express a family-internal phylogenetic relationship. In the Dhegihan languages, this series either remained preaspirated or converted the cluster into a geminate.{{sfn|Rankin|Carter|Jones|1998|p=367}}

Because the development of the stop series is so transparent, the consonant inventory is sometimes presented in a minimalist fashion, which removes the complex stop series and glottalized forms.{{sfn|Blevins|Egurtzegi|Ullrich|2020|pp=326–327}} Rankin describes the minimalist form without phonological conditioning as pre-Proto-Siouan since the language may have had a more parsimonious inventory at an earlier date. This inventory is also a closer match to that of the Catabaw language.{{sfn|Rankin|Carter|Jones|1998|p=373}} The minimalist form is as follows:{{sfn|Rankin|Carter|Jones|1998|p=373}}{{sfn|Blevins|Egurtzegi|Ullrich|2020|p=327}}

Accent was typically placed on the second syllable of a Proto-Siouan word.{{multiref|{{harvnb|Larson|2016|p=66}}.|{{harvnb|Rankin|Carter|Jones|1998|p=370}}.|{{harvnb|Campbell|1997|p=142}}.}} The stressed vowel was typically long, though this is not universal.{{sfn|Rankin|Carter|Jones|1998|p=370}} The language's syllable structure was probably CCV, though these syllable-initial clusters are typically bimorphemic and roots routinely comprise CV structures.{{multiref|{{harvnb|Rankin|1996|p=120}}.|{{harvnb|Mirzayan|2023|p=1470}}.|{{harvnb|Kasak|2024|p=87}}.}} In Mandan and Lakota, for example, the Proto-Siouan prefixes {{lang|sio|*wa-}}, marking inanimate absolutives and indefinite third-person objects, and {{lang|sio|*wi-}}, marking animals, are often collapsed into a single prefix {{lang|sio|p-}} independently in both languages, leading to a CCV syllable cluster. Examples include Proto-Siouan {{lang|sio|*wišį́:ka}} ('flying squirrel') becoming Lakota {{lang|lkt|pšįčá}} and Proto-Siouan {{lang|sio|*warį́}} ('water') becoming Mandan {{lang|mhq|wrį́ʔ}}.{{sfn|Rankin|1996|pp=119–120}}{{efn|The Mandan word for 'water' is {{lang|mhq|miní}} ({{IPA|mhq|mĩˈnĩ|pron|small=no}}).{{sfn|Kasak|2024|p=76}} The form given by {{harvp|Rankin|1996}} shows its underlying representation.{{sfn|Kasak|2024|pp=76, 123, 160}} For further discussion of Mandan phonological processes, see {{harvp|Kasak|2024}}.}} Other CCV roots are often the result of phonesthemic forms, a kind of sound symbolism used for groups of sounds or sound-producing motions.{{sfn|Rankin|1996|pp=120–121}} Earlier research suggested that Proto-Siouan had syllable-final glottal stops, but the evidence for these codas actually suggest they are actually the result of excrescence between vowels rather than preserved liaison.{{sfn|Kasak|2024|p=92}} Some reconstructed CVC clusters have been identified, but they are incredibly rare and almost exclusively the result of apocopic root extensions, though several are semantically obscure.{{sfn|Rankin|1996|pp=120, 125}}

Proto-Siouan had at least two contrastive tones: high, which is marked with an acute accent (◌́) on the vowel, and non-high, which is unmarked. It is possible that the language also had a falling tone, marked with a circumflex (◌̂).{{sfn|Rankin|Carter|Jones|1998|p=366}} Although the existence of a falling tone is common areally and typologically, Proto-Siouan is not typically reconstructed as having a falling tone. It is possible that the falling tone existed at an earlier point, perhaps in pre-Proto-Siouan, and the tone's interation with plain stops resulted in the glottalized stop series.{{sfn|Rankin|Carter|Jones|1998|pp=368–369}}{{sfn|Mirzayan|2023|p=1472}} If the accented vowel had a falling tone, it usually lost this tone and became glottalized.{{sfn|Rankin|Carter|Jones|1998|pp=370–371}} Examples of this process include the reconstructed form {{lang|sio|*kû}}, meaning 'give'. In Proto-Siouan, this falling tone shifted to {{lang|sio|*kuʔ}} in Proto–Missouri Valley Siouan and Proto-Mandan, exhibiting a non-high tone with an excrescent word-final glottal stop. In modern Crow, the glottal stop was vocalized leading to {{lang|cro|kúu}}, reflecting a long vowel with a high tone; modern Mandan and Hidatsa maintained the syllable-final stop.{{sfn|Rankin|Carter|Jones|1998|pp=368–369}} In the Mississippi Valley Siouan languages, these excrescent glottal stops metathesized with the vowel continued as a class of glottalized stops, while in Ohio Valley Siouan the stop appears to have metathesized to the onset, leading to unique outcomes in the daughter languages there including an initial prothetic vowel, as in Ofo, or prenasalized consonants in onset, as in Tutelo.{{sfn|Rankin|Carter|Jones|1998|p=369}}

{{broader|Apophony}}

All attested Siouan languages express a final-vowel root alternation known as ablaut which is reconstructable to Proto-Siouan.{{sfn|Mirzayan|2023|p=1467}} Typically, this alternation is between {{lang|sio|-a}} and {{lang|sio|-e}}, though some languages also include a word-final {{lang|sio|-i}} or {{lang|sio|-ĩ}}. There is no clear phonological condition under which this ablaut occurs, though they may be determined by the following word, a suffix, or a postclitic.{{sfn|Mirzayan|2023|p=1467}} The ablaut can be seen in examples from Lakota, where {{lang|lkt|káğe}} ('s/he made it'), {{lang|lkt|káğa he?}} ('did s/he make it?'), and {{lang|lkt|káğiŋ kte}} ('s/he will make it') show the tripartite division, all derived from an ablauting root – {{lang|lkt|káğA}} ('to make something') – where the capital A signifies the alternating vowel.{{sfn|Mirzayan|2023|pp=1467–1468}}

{{broader|Sound symbolism}}

The Siouan languages exhibit what is called "fricative-graded sound symbolism", sometimes termed "spirant gradation", a pervasive kind of sound symbolism using fricative consonants.{{sfn|Mirzayan|2023|p=1469}}{{sfn|Jones|1990|p=505}} The pervasiveness of this symbolic use of language makes reconstruction back to Proto-Siouan possible.{{sfn|Campbell|1997|pp=226, 340}} This sound symbolism is used to express gradation in intensity, volume, roughness, and other similar concepts.{{sfn|Mirzayan|2023|p=1469}}{{sfn|Jones|1990|pp=505–506}} In Lakota, for example, the root set meaning 'crack' has several forms based on the intensity of the damage: {{lang|lkt|-suzA-}} for a single crack, {{lang|lkt|-šužA-}} for a few cracks or a bad bruising, and {{lang|lkt|-ȟuǧA-}} for fractured or crushed.{{sfn|Mirzayan|2023|p=1469}}

Proto-Siouan also contained a series of phonesthemic root-initial clusters used to describe certain kinds of sounds or sound-producing motions. Like the spirant gradation previously described, these roots often differ through the realization of the vowel, of spirant gradation, or as a result of both.{{sfn|Rankin|1996|pp=120–121}} Examples include series symbolizing ripping – {{lang|sio|*sré-}} ('split'), {{lang|sio|*šré-}} ('split, shred'), and {{lang|sio|*xré-}} ('rip, tear') – and series symbolizing slippery motions or actions – {{lang|sio|*srą́-}} ('dribble'), {{lang|sio|*srí-}} ('ooze out, slurp, lick'), {{lang|sio|*srú-}} ('slide, masturbate').{{sfn|Rankin|1996|pp=120–121}} These series are sometimes reconstructed with an {{lang|sio|*l}} instead of an {{lang|sio|*r}} and are similar to the English-language sl- equivalents, such as slime, sludge, slick, and slobber.{{sfn|Rankin|1996|p=120}}

Given the widespread use of object–verb syntax among the Siouan languages, Proto-Siouan almost certainly had a constituent word order of subject–object–verb.{{sfn|Rankin|Carter|Jones|1998|p=373}} It was head-marking and adjectives followed their head nouns.{{sfn|Rankin|Carter|Jones|1998|p=373}} Typologically, the language was a somewhat agglutinative language with a tendency towards simple incorporation, though its output is more in line with basic compounding.{{sfn|Rankin|Carter|Jones|1998|p=371}} Morphosyntactically, it had active–stative alignment.{{sfn|Munro|2015|p=34}} The Ohio Valley Siouan languages, comprising the attested Ofo and Biloxi languages, however, are the known to have had a different alignment, but they are unique in this way among Siouan languages.{{sfn|Munro|2015|p=34}}

Verbs in Proto-Siouan were inflected for person, number, aspect, mode, tense, instrument, and likely other markers. Attested Siouan languages mark variously for grammatical gender, evidentiality, and quotativity, though it is unclear which of these were present in Proto-Siouan, if any.{{sfn|Rankin|Carter|Jones|1998|p=373}} The verb template in Proto-Siouan is somewhat differentiated from those of its daughter languages as many languages developed innovative forms to the original template.{{sfn|Rankin|Carter|Jones|1998|pp=373–374}} At least three locative prefixes – {{lang|sio|*a-}} ('on, at'), {{lang|sio|*o-}} ('in'), and {{lang|sio|*i-}} ('toward') – as well as the general instrumental prefix {{lang|sio|*í-}}, were probably proclitics and not true affixes in Proto-Siouan, or even pre-Proto-Siouan, as evidence indicates that they were accented long vowels.{{sfn|Rankin|Carter|Jones|1998|p=374}} The language's first- and second-person agent markers – {{lang|sio|*w(a)-}} and {{lang|sio|*y(a)-}}, respectively – preceded agent markers; these markers similarly avoid typical phonological processes so they are also believed to have been proclitics.{{multiref2|For the order of the markers and their probable origins as proclitics, see {{harvnb|Rankin|Carter|Jones|1998|p=374}}.|For the markers themselves, see {{harvnb|Rudes|2015|p=86}} and {{harvnb|Rankin|1996|pp=122–123}}.}} The only reconstructable template elements are the root, first- and second-person agent markers, and dative–possessive markers.{{sfn|Rankin|1996|p=123}}

Among the Siouan languages, instrumentally-prefixed verbs comprise the vast majority of active verbs.{{sfn|Jones|1990|p=505}} These verbs comprise a fusion of a root verb, typically a bound morpheme, and a prefix which expresses the manner by which the action is achieved, such as {{lang|sio|*aRá}} 'by heating' or {{lang|sio|*ra}} 'using the mouth'.{{sfn|Jones|1990|p=505}}{{sfn|Rankin|Carter|Jones|1998|pp=374–375}} In Proto-Siouan, these prefixes probably began as either proclitics or independent verbs, as evidence shows that these prefixes do not undergo the same phonological changes found in other prefixes.{{sfn|Rankin|Carter|Jones|1998|p=374}} They may have also been derived from some kind of compounding or some other opaque derivational system.{{sfn|Jones|1990|p=506}} Because they behave differently from other affixes, they are sometimes termed "root extensions", especially since the root verb cannot usually stand on its own without them.{{sfn|Jones|1990|p=506}}

Proto-Siouan made use of a class of verbs to mark the continuative aspect. These verbs – {{lang|sio|*rą́:ke}} ('sit'), {{lang|sio|*rahé}} ('stand', inanimate), {{lang|sio|*hą́:ke}} ('stand', animate), {{lang|sio|*ʔų́:ke}} ('lie'), and {{lang|sio|*rį́:}} ('move') – are used in virtually all Siouan languages to mark the continuative aspect.{{sfn|Rankin|2004|p=203, 209}} In all of the attested Dhegihan languages, however, these functions were lost, but the terms later came to be used as a kind of noun class marking. For example, in Omaha–Ponca, a singular, non-agentive animate noun was marked with {{lang|oma|ðį}}, as in {{lang|oma|tté-žįga ðį}} ('the [moving] buffalo calf'), while singular nouns – irrespective of animacy – seen "lying down" in some sense, were marked with {{lang|oma|khe}}, as in {{lang|oma|waˀú khe}} ('the [reclining] woman') or {{lang|oma|né khe}} ('the lake').{{multiref2|For the loss of this feature in this class of verbs, see {{harvnb|Rankin|2004|p=217}}.|For everything else, see {{harvnb|Rankin|2004|pp=211–212}}.}}

{{further|Yuchi language}}

The Yuchi language, once spoken around the Upper Tennessee Valley before the Yuchis were displaced, is generally considered a language isolate, but the relationship between Yuchi and the Siouan languages has been long debated.{{sfn|Kasak|2016|pp=5, 11}}{{sfn|Campbell|1997|p=150}} Evidence shows that the Yuchi and Catawba peoples, as well as some other Siouan-speaking peoples, shared a geographic area around the Eastern United States for a significant period prior to the exploration and colonization of the region by Europeans.{{sfn|Kasak|2016|pp=12–13}} The first arguments for the linguistic relationship came from Edward Sapir in 1929, based on a relatively small number of supposed cognates.{{sfn|Kasak|2016|p=15}} In 1998, Robert L. Rankin also evaluated the relationship, focusing more on the relative morphological resemblances.{{sfn|Kasak|2016|p=15}}

Arguments in favor of the relationship have focused on lexical and morphological similarities.{{sfn|Chafe|1976|pp=53–54}} For example, noun classes found in both are unusually similar, including the Siouan animate non-human prefix {{lang|sio|*wi-}} and its Yuchi analog {{lang|yuc|we-}} and the Siouan impersonal human marker {{lang|sio|*ko-}} and Yuchi {{lang|yuc|go-}}.{{sfn|Rankin|1996|p=126}} Another argument in favor of the relationship is that, like the Siouan languages, Yuchi exhibits fricative-graded sound symbolism in a similar fashion.{{sfn|Mirzayan|2023|p=1469}}{{sfn|Kasak|2016|p=31}} Examples in Yuchi include {{lang|yuc|'ispi}} ('black') as compared to {{lang|yuc|'išpi}} ('dirty') and {{lang|yuc|čʰaɬa}} ('pink') as compared to {{lang|yuc|tsʰaɬa}} ('red').{{sfn|Kasak|2016|p=31}} Likewise, Yuchi exhibits a similar ablauting to the Siouan languages, including the use of the final nasal vowel to mark the future tense, similar to its use in Lakota.{{sfn|Mirzayan|2023|pp=1468–1469}}{{sfn|Kasak|2016|pp=31–32}} A relationship between the Siouan languages and Yuchi is among the more accepted proposals among Siouanists.{{sfn|Kasak|2016|p=13}} If the relationship is phylogenetic, new models suggest that Yuchi can be identified a second phylogenetic prong of the Catawban subfamily, rather than as a third prong of the larger Siouan–Catawban family tree.{{sfn|Coen|2021|p=14}}{{sfn|Kasak|2024|p=19}}

{{main|Macro-Siouan}}

Among the first to propose a larger relationship between Siouan and other indigenous languages of the Americas was Robert Latham, an English ethnologist, who first attempted to link the Siouan languages with Iroquoian in 1856, though he also suspected that Catabaw, Cherokee, Choctaw, and Caddo may also be distantly related.{{sfn|Kasak|2016|p=13}} After researching several of the treaties signed by the Cayuga, Lewis H. Morgan came to believe that the Iroquoian languages were descended from the Dakotan languages, formally proposing the link in 1871.{{sfn|Kasak|2016|p=13}}{{sfn|Chafe|1976|p=43}} Both of these approaches, however, did not enjoy widespread acceptance; they were built on shakey data and small sets of comparanda.{{sfn|Kasak|2016|p=13}}

Sapir's 1929 proposal to link Yuchi to the Siouan languages did not stop there; he proposed what he called the "Hokan-Siouan languages", now known as "Macro-Siouan", comprising the Siouan–Catawban, Iroquoian, Caddoan, and Muskogean languages, along with several isolates including Natchez, Tunica, and several others.{{sfn|Kasak|2016|p=13}} Similarly, his student Mary Haas attempted to link the putative Gulf languages – comprising the Muskogean languages, Natchez, Tunica, Chitimacha, and Atakapa – with the Siouan and the Algonquian languages in the 1950s.{{sfn|Chafe|1976|pp=53–54}} This hypothesis, however, does not have widespready support among linguists.{{sfn|Rankin|2002|p=195}}

• Classification of the Indigenous languages of the Americas
• Dorsey's law

{{notelist}}

{{reflist}}

{{refbegin|30em|indent=yes}}

• {{cite book |last=Sutton |first=Logan |chapter=Linguistic Evidence of Contact between Northern Caddoan and Siouan Languages: Arikara-Pawnee Verbal Classifiers |pages=315–344 |editor-last=Andersson |editor-first=Rani-Henrik |editor-last2=Veyrié |editor-first2=Thierry |editor-last3=Sutton |editor-first3=Logan |title=Great Plains Ethnohistory: New Interdisciplinary Approaches |publisher=University of Nebraska Press |publication-place=Lincoln, Nebraska |url=https://muse.jhu.edu/book/123847 |url-access=subscription |date=2024 |isbn=978-1-4962-4211-2}}
• {{cite journal |last1=Blevins |first1=Juliette |author-link1=Juliette Blevins |last2=Egurtzegi |first2=Ander |last3=Ullrich |first3=Jan |title=Final obstruent voicing in Lakota: Phonetic evidence and phonological implications |journal=Language|volume=96 |issue=2 |date=2020 |issn=1535-0665 |doi=10.1353/lan.2020.0022 |doi-access=free |pages=294–337 |url=https://muse.jhu.edu/article/757630/pdf }}
• {{cite book |last=Campbell |first=Lyle |title=American Indian Languages: The Historical Linguistics of Native America |publisher=Oxford University Press |series=Oxford Studies in Anthropological Linguistics |volume=4 |date=1997 |isbn=978-0-19-509427-5}}
• {{cite book |last=Chafe |first=Wallace L. |author-link=Wallace Chafe |title=The Caddoan, Iroquoian, and Siouan Languages |publisher=De Gruyter |date=1976 |isbn=978-90-279-3443-7 |doi=10.1515/9783110804669 |url=https://www.degruyter.com/document/doi/10.1515/9783110804669/html |url-access=subscription}}
• {{cite book |last1=Collette |first1=Vincent |last2=Kennedy |first2=Wilma |url=https://muse.jhu.edu/book/100260 |url-access=subscription |title=A Concise Dictionary of Nakoda (Assiniboine) |publisher=University of Nebraska Press |publication-place=Lincoln, Nebraska |date=2023 |isbn=978-1-4962-3272-4}}
• {{cite book |last=Mirzayan |first=Armik |chapter=56. Sketch of the Siouan Language Family |pages=1447–1518 |editor-last=Dagostino |editor-first=Carmen |editor-last2=Mithun |editor-first2=Marianne |editor-link2=Marianne Mithun |editor-last3=Rice |editor-first3=Keren |title=The Languages and Linguistics of Indigenous North America: A Comprehensive Guide, Volume 2 |volume=13.2 |series=The World of Linguistics |publisher=De Gruyter |date=2023 |isbn=978-3-11-071274-2 |doi=10.1515/9783110712742 |url=https://www.degruyter.com/document/doi/10.1515/9783110712742/html |url-access=subscription}}
• {{Cite conference| publisher = University of Kansas Department of Linguistics| conference = Mid-America Linguistics Conference| pages = 505–517| editor-first=Frances |editor-last=Ingemann |last = Jones| first = A. Wesley| title = The Case for Root Extensions in Proto-Siouan| book-title = 1990 Mid-America Linguistics Conference Papers| location = Lawrence, Kansas| date = 1990 |url=https://csd.clld.org/static/Jones_root_extensions.pdf}}
• {{cite journal |last=Kaufman |first=David V. |title=Biloxi Origins |journal=Native South |volume=11 |issue=1 |date=2018 |issn=2152-4025 |doi=10.1353/nso.2018.0005 |pages=145–157 |url=https://muse.jhu.edu/article/699968 |url-access=subscription}}
• {{cite book |last=Kasak |first=Ryan M. |location=Berlin |publisher=Language Science Press |series=Comprehensive Grammar Library |volume=10 |title=A Grammar of Mandan |date=2024 |url=http://langsci-press.org/catalog/book/446 |isbn=978-3-96110-495-6 |issn=2749-7798}} {{open access}}
• {{cite conference |editor-last=Kasak |editor-first=Ryan M. |editor-last2=Rudin |editor-first2=Catherine |editor-last3=Mirzayan |editor-first3=Armik |editor-last4=Dutta |editor-first4=Samiron |date=2021 |url=http://www.siouan.org/proceedings/sclc41 |title=Proceedings of the 41st Siouan and Caddoan Languages Conference |conference=Siouan and Caddoan Languages Conference |location=Norman, Oklahoma |issn=2641-9904}}
• {{harvc |last=Coen |first=Noah Michael |chapter=(Para-)Adpositional Morphosyntax in Siouan: A Case Study of Lakhota-Dakota-Nakota, Catawba, and Crow |pages=13–58 |year=2021 |in=Kasak |in2=Rudin |in3=Mirzayan |in4=Dutta }}
• {{cite journal |last1=Miestamo |first1=Matti |last2=Bakker |first2=Dik |last3=Arppe |first3=Antti |title=Sampling for variety |journal=Linguistic Typology |volume=20 |issue=2 |date=2016 |issn=1430-0532 |doi=10.1515/lingty-2016-0006 |doi-access=free |pages=233–296}}
• {{cite book |editor-last=Picone |editor-first=Michael D. |editor-last2=Davies |editor-first2=Catherine Evans |title=New Perspectives on Language Variety in the South: Historical and Contemporary Approaches|publisher=University of Alabama Press |url=https://muse.jhu.edu/book/38807 |url-access=subscription |publication-place=Tuscaloosa, Alabama |date=2015 |isbn=978-0-8173-8736-5}}
• {{harvc |last=Munro |first=Pamela |chapter=2. American Indian Languages of the Southeast: An Introduction |pages=21–42 |year=2015 |in=Picone |in2=Davies }}
• {{harvc |last=Rankin |first=Robert L. |author-link=Robert L. Rankin |chapter=4. The Ofo Language of Louisiana: Recovery of Grammar and Typology |pages=52–71 |year=2015 |in=Picone |in2=Davies }}
• {{harvc |last=Rudes |first=Blair A. |chapter=6. Pre-Columbian Links to the Caribbean: Evidence Connecting Cusabo to Taíno |pages=82–93 |year=2015 |in=Picone |in2=Davies }}
• {{cite journal |last=Rankin |first=Robert L. |author-link=Robert L. Rankin |title=Deeper Genetic Relationships in North America: Some Tempered Pessimism |journal=Annual Meeting of the Berkeley Linguistics Society |volume=22 |issue=2 |date=1996 |issn=2377-1666 |doi=10.3765/bls.v22i2.1362 |doi-access=free |pages=117–128 |url=https://journals.linguisticsociety.org/proceedings/index.php/BLS/article/download/1362/1146 }}
• {{cite conference |last1=Rankin |first1=Robert L. |author-link1=Robert L. Rankin |last2=Carter |first2=Richard T. |last3=Jones |first3=A. Wesley |editor-last=Li |editor-first=Xingzhong |editor-last2=Lopez |editor-first2=Luis |editor-last3=Stroik |editor-first3=Tom |date=1998 |title=Proto-Siouan Phonology and Grammar |url=https://csd.clld.org/static/Rankin_Carter_Jones_Proto-Siouan_Phonology.pdf |book-title=Papers from the 1997 Mid-America Linguistics Conference |conference=Mid-America Linguistics Conference |location=Columbia, Missouri |pages=366–375 |publisher=University of Missouri}}
• {{cite journal |last=Rankin |first=Robert L. |author-link=Robert L. Rankin |title=The history and development of Siouan positional with special attention to polygrammaticalization in Dhegiha |journal=Sprachtypologie und Universalienforschung |volume=57 |issue=2–3 |date=2004 |issn=2196-7148 |doi=10.1524/stuf.2004.57.23.202 |url=https://www.degruyter.com/document/doi/10.1524/stuf.2004.57.23.202/html |url-access=subscription}}
• {{cite book |last1=Rood |first1=David |last2=Koontz |first2=John E. |editor-last=Frawley |editor-first=William |editor-last2=Hill |editor-first2=Kenneth C. |editor-last3=Munro |editor-first3=Pamela |title=Making Dictionaries: Preserving Indigenous Languages of the Americas |publisher=University of California Press |publication-place=Berkeley |date=2002 |isbn=978-0-520-22996-9 |chapter=Chapter Eleven: The Comparative Siouan Dictionary Project |chapter-url=https://csd.clld.org/static/Rood_Koontz_2002_CSD.pdf |url=https://www.ucpress.edu/books/making-dictionaries/paper |url-access=subscription |pages=259–281 }}
• {{cite book |editor-last=Rood |editor-first=David |editor-last2=Boyle |editor-first2=John |title=Siouan Languages and Linguistics: Selected Papers by Robert L. Rankin |publisher=Brill |date=2020 |isbn=978-90-04-40628-5 |doi=10.1163/9789004406285 |url=https://brill.com/view/title/54832 |url-access=subscription}}
• {{cite conference |last=Rankin |first=Robert L. |author-link=Robert L. Rankin |date=2003 |title=On Siouan Chronology |work= |book-title= |conference=Research Center for Linguistic Typology |location=Melbourne |publisher= }}
• {{cite book |last=Rankin |first=Robert L. |author-link=Robert L. Rankin |date=2002 |title=A Diachronic Perspective on Active/Stative Alignment in Siouan |location=Lawrence, Kansas |publisher=University of Kansas and Research Center for Linguistic Typology |pages=181–216 }}
• {{cite book|editor-last=Rudin |editor-first=Catherine |editor-last2=Gordon |editor-first2=Bryan J. |publisher=Language Science Press |series=Studies in Diversity Linguistics |volume=10 |location=Berlin |title=Advances in the Study of Siouan Languages and Linguistics |date=2016 |doi=10.17169/LANGSCI.B94.118 |url=http://langsci-press.org/catalog/book/94 |doi-access=free |isbn=978-3-946234-37-1 |issn=2363-5568}} {{open access}}
• {{harvc|last=Kasak |first=Ryan M. |chapter=Chapter 1: A distant genetic relationship between Siouan–Catawban and Yuchi |pages=5–38 |year=2016 |in=Rudin |in2=Gordon }}
• {{harvc|last=Kaufman |first=David |chapter=Chapter 2: Two Siouan languages walk into a sprachbund |pages=39–62 |year=2016 |in=Rudin |in2=Gordon }}
• {{harvc|last=Larson |first=Rory |chapter=Chapter 3: Regular sound shifts in the history of Siouan |pages=63–82 |year=2016 |in=Rudin |in2=Gordon }}
• {{cite journal |last1=Schillaci |first1=Michael A. |last2=Kopris |first2=Craig |last3=Wichmann |first3=Søren |author-link3=Søren Wichmann |last4=Dewar |first4=Genevieve |title=Linguistic Clues to Iroquoian Prehistory |journal=Journal of Anthropological Research |volume=73 |issue=3 |date=2017 |issn=0091-7710 |doi=10.1086/693055 |pages=448–485 |url=https://www.journals.uchicago.edu/doi/10.1086/693055 |url-access=subscription}}

{{refend}}

• {{cite conference |editor-last=Kasak |editor-first=Ryan M. |date=2018 |url=https://neiudc.neiu.edu/cgi/viewcontent.cgi?article=1001&context=sclc |title=Proceedings of the 38th Siouan and Caddoan Languages Conference |conference=Siouan and Caddoan Languages Conference |location=Chicago |issn=2641-9904 |publisher=Northeastern Illinois Univeristy Linguistics Department}}
• {{harvc |last=Kasak |first=Ryan M. |chapter=Topic and focus in Mandan |pages=59–89 |year=2021 |in=Kasak |in2=Rudin |in3=Mirzayan |in4=Dutta }}
• {{cite conference |last=Ko |first=Edwin |date=2021 |title=A Bayesian phylogenetic study of the Siouan language family using typological data |url=https://eddersko.com/assets/KoSCLC41Slides.pdf |work= |conference=41st Siouan and Caddoan Languages Conference |location=Norman, Oklahoma |publisher=University of Oklahoma Department of Languages, Literatures, and Linguistics }}
• {{cite conference |editor-last=Linnamae |editor-first=Urve |editor-last2=Ervin |editor-first2=A. M. |editor-last3=Walker |editor-first3=E. G. |date=1983 |url=https://lx.berkeley.edu/sites/default/files/koontz_-_siouan_syncopating_r-stems.pdf |book-title=Proceedings of the Second Siouan Languages Conference |title=Siouan Syncopating *r-Stems |conference=Siouan Languages Conference |volume=13 |issn=2641-9904}}
• {{cite journal |last=Griffin |first=James B. |author-link=James Bennett Griffin |title=On the Historic Location of the Tutelo and the Mohetan in the Ohio Valley |journal=American Anthropologist |publisher=American Anthropological Association |volume=44 |issue=2 |year=1942 |issn=00027294 |jstor=663025 |pages=275–280 |url=http://www.jstor.org/stable/663025 |url-access=subscription}}
• {{cite journal |last=Hale |first=Horatio |author-link=Horatio Hale |title=The Tutelo Tribe and Language |journal=Proceedings of the American Philosophical Society |publisher=American Philosophical Society |volume=21 |issue=114 |year=1883 |issn=0003049X |jstor=982359 |pages=1–47 |url=http://www.jstor.org/stable/982359 |jstor-access=free}}
• {{cite journal |last=Matthews |first=G. H. |title=Proto-Siouan Kinship Terminology |journal=American Anthropologist |publisher=American Anthropological Association |volume=61 |issue=2 |year=1959 |issn=0002-7294 |jstor=665096 |pages=252–278 |doi=10.1525/aa.1959.61.2.02a00050 |url=http://www.jstor.org/stable/665096 |url-access=subscription}}
• {{cite journal |last=Matthews |first=G. H. |title=Some Notes on the Proto-Siouan Continuants |journal=International Journal of American Linguistics |publisher=University of Chicago Press |volume=36 |issue=2 |year=1970 |issn=00207071 |jstor=1264668 |pages=98–109 |url=http://www.jstor.org/stable/1264668 |url-access=subscription}}
• {{cite conference |last=Rankin |first=Robert L. |author-link=Robert L. Rankin |date=1995 |title=On Mississippi Valley Siouan "Ablaut" |url=https://listserv.linguistlist.org/pipermail/siouan/attachments/20130916/79e92911/attachment.pdf |work= |conference=Siouan and Caddoan Linguistics Conference |location=Albuquerque |publisher= }}
• {{Cite book| publisher = Max Planck Institute for Evolutionary Anthropology| editor-first= Robert L. |editor-last=Rankin |editor-link=Robert L. Rankin |editor-first2=Richard T. |editor-last2=Carter |editor-first3=A. Wesley |editor-last3=Jones |editor-first4=John E. |editor-last4=Koontz |editor-first5=David S. |editor-last5=Rood |editor-first6=Iren |editor-last6=Hartmann | title = Comparative Siouan Dictionary| location = Leipzig| date = 2015 |url=https://csd.clld.org/}} {{open access}}
• {{cite book |last1=Silver |first1=Shirley |last2=Miller |first2=Wick R. |title=American Indian Languages: Cultural and Social Contexts |publisher=University of Arizona Press |publication-place=Tucson |date=1997 |isbn=978-0-8165-1802-9}}
• {{cite journal |last=Speck |first=Frank G. |author-link=Frank Speck |title=The Question of Matrilineal Descent in the Southeastern Siouan Area |journal=American Anthropologist |publisher=[American Anthropological Association, Wiley] |volume=40 |issue=1 |year=1938 |issn=00027294 |jstor=661786 |pages=1–12 |url=http://www.jstor.org/stable/661786 |url-access=subscription}}
• {{cite journal |last=Sturtevant |first=William C. |author-link=William C. Sturtevant |title=Siouan Languages in the East |journal=American Anthropologist |publisher=[American Anthropological Association, Wiley] |volume=60 |issue=4 |year=1958 |issn=00027294 |jstor=665680 |pages=738–743 |url=http://www.jstor.org/stable/665680 |url-access=subscription}}
• {{cite journal |last=Swanton |first=John R. |author-link=John R. Swanton |title=New light on the early history of the Siouan peoples |journal=Journal of the Washington Academy of Sciences |publisher=Washington Academy of Sciences |volume=13 |issue=3 |year=1923 |issn=00430439 |jstor=24532662 |pages=33–43 |url=http://www.jstor.org/stable/24532662 |jstor-access=free}}
• {{cite journal |last=Swanton |first=John R. |author-link=John R. Swanton |title=Siouan Tribes and the Ohio Valley |journal=American Anthropologist |publisher=American Anthropological Association |volume=45 |issue=1 |year=1943 |issn=00027294 |jstor=662865 |pages=49–66 |url=http://www.jstor.org/stable/662865 |url-access=subscription}}
• {{cite journal |last=Taylor |first=Allan R. |title=On Verbs of Motion in Siouan Languages |journal=International Journal of American Linguistics |publisher=University of Chicago Press |volume=42 |issue=4 |year=1976 |issn=00207071 |jstor=1264261 |pages=287–296 |url=http://www.jstor.org/stable/1264261 |url-access=subscription}}
• {{cite journal |last=Voegelin |first=C. F. |author-link=Charles F. Voegelin |title=Internal Relationships of Siouan Languages |journal=American Anthropologist |publisher=[American Anthropological Association, Wiley] |volume=43 |issue=2 |year=1941 |issn=00027294 |jstor=662955 |pages=246–249 |url=http://www.jstor.org/stable/662955 |url-access=subscription}}
• Hans Wolff's four-part series on Siouan comparanda:
• {{cite journal |last=Wolff |first=Hans |title=Comparative Siouan I |journal=International Journal of American Linguistics |publisher=University of Chicago Press |volume=16 |issue=2 |year=1950 |issn=00207071 |jstor=1262849 |pages=61–66 |url=http://www.jstor.org/stable/1262849 |url-access=subscription}}
• {{cite journal |last=Wolff |first=Hans |author-mask=2 |title=Comparative Siouan II |journal=International Journal of American Linguistics |publisher=University of Chicago Press |volume=16 |issue=3 |year=1950 |issn=00207071 |jstor=1263051 |pages=113–121 |url=http://www.jstor.org/stable/1263051 |url-access=subscription}}
• {{cite journal |last=Wolff |first=Hans |author-mask=2 |title=Comparative Siouan III |journal=International Journal of American Linguistics |publisher=University of Chicago Press |volume=16 |issue=4 |year=1950 |issn=00207071 |jstor=1262899 |pages=168–178 |url=http://www.jstor.org/stable/1262899 |url-access=subscription}}
• {{cite journal |last=Wolff |first=Hans |author-mask=2 |title=Comparative Siouan IV |journal=International Journal of American Linguistics |publisher=University of Chicago Press |volume=17 |issue=4 |year=1951 |issn=00207071 |jstor=1263103 |pages=197–204 |url=http://www.jstor.org/stable/1263103 |url-access=subscription}}