Dalmatius

:This article deals with the Caesar (335-337). For the censor Flavius Dalmatius, father of the Caesar, see Flavius Dalmatius. For saints with this name, see Saint Dalmatius (disambiguation).

{{Infobox Roman emperor

| name = Flavius Dalmatius

| full name =

| regnal name =

| title = Caesar

| titletext = (18 September 335 – June 337)

| image = Delmatius Coin Abverse.jpg

| caption = Follis of Dalmatius minted in Aquileia.
Legend: {{Smallcaps|{{Abbreviation|fl·|FLAVIUS}} {{Abbreviation|delmatius·}} {{Abbreviation|nob·|NOBILISSIMUS}} {{Abbreviation|c·|CAESAR}}}}

| predecessor =

| successor =

| spouse 1 =

| spouse 2 =

| issue =

| dynasty = Constantinian

| father = Dalmatius the Censor

| mother =

| birth_date =

| birth_place =

| death_date = June 337

| death_place =

| place of burial =

}}

Flavius Dalmatius (died June 337),{{Cite book |last=Doležal |first=Stanislav |url=https://books.google.com/books?id=4hVuEAAAQBAJ&pg=PA399 |title=The Reign of Constantine, 306–337: Continuity and Change in the Late Roman Empire |date=2022 |publisher=Springer Nature |isbn=978-3-030-97464-0 |language=en}} often spelled Delmatius on contemporary coins, was a Caesar of the Roman Empire from 335 to 337, and member of the Constantinian dynasty.

Dalmatius was the nephew of Constantine the Great. His father, also named Flavius Dalmatius, was the half-brother of Constantine and served as censor. Dalmatius and his brother Hannibalianus were educated at Tolosa (Toulouse) by rhetor Exuperius.

File:Impero Romano da maggio a settembre 337.png: from west to east, the territories of Constantine II, Constans I, Dalmatius and Constantius II. After the death of Constantine I (May 337), Dalmatius was killed and his territory divided between Constans and Constantius.]]

On 18 September 335, he was raised to the rank of Caesar by his uncle, with the control of Thracia, Achaea and Macedonia. Dalmatius died in early summer 337, killed by his own soldiers. It is possible that his death was related to the purge that hit the imperial family at the death of Constantine, and organized by Constantius II with the aim of removing any possible claimant to imperial power other than the sons of the late emperor.