empty diagonal
{{Short description|Band of low-density population in France}}
Image:Carte démographique de la France.svg
The empty diagonal ({{langx|fr|diagonale du vide}}) is a band of low-density population that stretches from the French department of the Landes in the southwest to the Meuse in the northeast. The diagonal's population density is very low compared to the rest of France.
Description
The low population density (less than 30/km², or 78/mi²) is caused largely by the rural exodus and urbanisation of the 19th and 20th centuries. Some commentators{{cite book |author=Jean-Claude Bontron |title=La France des faibles densités, II : Documentation bibliographique, Analyses d'études |year=1976 |publisher=SEGESA-ACEAR }} prefer to speak of a "low-density diagonal" ({{lang|fr|diagonale des faibles densités}}) and regard the term "empty diagonal" as both pejorative and exaggerated. Still, DATAR{{cite web |author=Gilles Fumey |url=http://cafe-geo.net/wp-content/uploads/france-en-diagonales.pdf |title=La France en diagonales|date=2009-10-26 |access-date=18 July 2016}}. used the term and it remains the most common term.
The pattern is more readily apparent at the departmental level than at the regional level.{{cite web |url=http://avenirural.wordpress.com/2012/07/10/le-massif-central-au-coeur-de-la-diagonale-du-vide-2/ |title=Le Massif Central : au cœur de la diagonale du vide }}{{cite web |url=http://geoconfluences.ens-lyon.fr/doc/territ/FranceMut/FranceMutVoc.htm | title=La France : des territoires en mutation }} It is part of a broader pattern of low population density that extends into Spain and Portugal and is known as the {{ill|continental diagonal|es|Diagonal continental}}.{{cite web |author=Rozenblat, C. |url=http://www.mgm.fr/PUB/Mappemonde/M495/MAILLE.pdf |title=Tissu d'un semi de villes européennes }}{{cite journal |author1=Yoann Doignon |author2=Sébastien Oliveau |author3=Isabelle Blöss-Widmer |title=L'Europe méridionale depuis 20 ans : dépeuplement, dépopulation et renouveau démographique |url=http://eps.revues.org/6171 |journal=Espace, Populations, Sociétés |year=2016 |issue=2015/3–2016/1 |doi=10.4000/eps.6171 |doi-access=free }}
History and evolution
Before the emergence of the empty diagonal, an earlier demographic feature was the Saint-Malo-Geneva line that ran from the northwest to the southeast and divided the industrial northeast from the agrarian southwest. Charles Dupin identified it in his 1837 treatise {{lang|fr|Forces productives et commerciales de la France}}.{{citation needed |date=February 2019}}
In 1947, the geographer Jean-François Gravier wrote of a "French desert" that corresponds, more or less, to the modern notion of the empty diagonal.{{citation needed |date=February 2019}}
Hervé Le Bras and Emmanuel Todd argue that the concept is no longer valid in the 21st century because of growth that is observed in some departments like Indre and Gers.{{cite book |author1=Hervé Le Bras |author1-link=Hervé Le Bras |author2=Emmanuel Todd |author2-link=Emmanuel Todd |title=Le Mystère français |publisher=Seuil |year=2013 |isbn=9782021102161 }} According to their analysis, the zone of negligible or negative population growth extends only from the Massif Central to Lorraine. However, an analysis at the level of cantons and communes indicates that the zone of decline extends beyond the Massif–Lorraine axis{{cite journal |url=https://journals.openedition.org/cybergeo/31641 |title=Is the French diagonal emptying? An exploratory spatial analysis of demographic decrease in France for the past 50 years |author1=Yoann Doignon |author2=Sébastien Oliveau |journal=European Journal of Geography |date=20 January 2016 |doi=10.4000/cybergeo.31641 |doi-access=free }} (translated from "{{lang|fr|La diagonale se vide ? Analyse spatiale exploratoire des décroissances démographiques en France métropolitaine depuis 50 ans}}", {{doi|10.4000/cybergeo.27439}}) and that the growth observed by Le Bras and Todd is fragile and driven by a temporary influx of retirees.{{citation needed |date=February 2019}}
Literature
La diagonale du vide is the title of a 2009 novel by Pierre Péju{{cite book |title=La diagonale du vide |author=Pierre Péju |year=2009 |author-link=Pierre Péju |isbn=9782070781034 |publisher=Éditions Gallimard, Collection Blanche }} in which an urban businessman seeks solitude in a cottage in Ardèche.
From 2015 to 2016, the author and blogger Mathieu Mouillet spent 18 months exploring the empty diagonal and meeting its inhabitants. His "exotic voyage" is presented by notes and photographs on his blog.{{cite web |title=La diagonale du vide |url=http://www.lesvoyagesdemat.com/diagonale-du-vide/ |author=Mathieu Mouillet }}
Gallery
Image:DepartementsFranceDensitePopulation.svg|Map of population density by department, showing the empty diagonal in blue.
Image:Estimations carroyees de population.png|Detailed map of population density, with the least populated areas in white.