Rouergue became a department in 1790, and was renamed Aveyron after the principal river flowing through it. Upon creation of the department of Tarn-et-Garonne in 1808, the canton of Saint-Antonin-Noble-Val was detached from the western extremity of Aveyron and transferred to the new department.
The province of Rouergue has a land area of 9,007 km² (3,478 sq. miles). At the 1999 census there were 269,774 inhabitants on the territory of the province of Rouergue, for a density of only 30 inh. per km² (78 inh. per sq. mile). The largest urban areas are Rodez, with 38,458 inhabitants in 1999; Millau, with 22,840 inhabitants in 1999; Decazeville, with 17,044 inhabitants in 1999; and Villefranche-de-Rouergue, with 12,561 inhabitants in 1999.