Tarn-et-Garonne (French pronunciation: [taʁn‿e ɡa.ʁɔn], Occitan: Tarn e Garona) is a department in the southwest of France. It is traversed by the Rivers Tarn and Garonne, from which it takes its name. This area was originally part of the former provinces of Quercy and Languedoc. The department was created in 1808 by Napoléon Bonaparte, with territory being taken from the departments of Lot, Haute-Garonne, Lot-et-Garonne, Gers and Aveyron. The department is mostly rural with fertile agricultural land in the broad river valley, but there are hilly areas to the south, east and north. The departmental prefecture is Montauban, and some of the other large communes include Castelsarrasin, Molières, Caussade, Valence-d'Agen and the medieval town of Lauzerte.
Quercy was part of Aquitania prima under the Romans, and Christianity was introduced during the 4th century. Early in the 6th century the area fell under the authority of the Franks, and in the 7th century became part of the autonomous Duchy of Aquitaine. At the end of the 10th century its rulers were the powerful counts of Toulouse. During the hostilities between England and France in the reign of Henry II of England, the English placed garrisons in the county, and by the 1259 Treaty of Paris lower Quercy came under the control of England. The kings of both England and France around this time tried to curry favour by adding to the privileges of the towns and the district. In 1360, the Treaty of Brétigny was signed and the whole of Quercy passed to England. However, in the 1440s the English were finally expelled by the newly created army of Charles VII of France. In the 16th century Quercy was a stronghold of the Protestants, and the scene of fierce religious conflicts. The civil wars of the reign of Louis XIII largely took place around Montauban.