Chablais was a province of the Duchy of Savoy. Its capital was Thonon-les-Bains.
Chablais was elevated to a duchy in 1311 by Henry VII, Holy Roman Emperor.
This region is currently divided into three territories, the Chablais savoyard, the Chablais valaisan, and the Chablais vaudois, and is now split across two countries: France (department of Haute-Savoie) and Switzerland (cantons of Valais and Vaud). The Chablais Alps is a mountain range situated between the two countries.