Pays in southwestern France around the town of Bazas, which is southeast of Bordeaux and WNW of Agen. Bazas lies south of the Garonne, but the Bazadais extended northwards over the river.
In the 9th century it was held by the Counts of Agen. After 936 much of it became part of the Duchy of Gascony, later absorbed by Aquitaine, while the rest remained linked to the Agenais. The Bishop of Agen had much of the power in the area, but in 1283 reached an agreement with the English King (and Duke of Aquitaine) to share power. The lordship of Albret later extended into the Bazadais.
The pays formed the diocese of Bazas, which belonged to the province of Auch and was suppressed in 1790.