Town and former Imperial lordship in southwest Baden-Württemberg, north of Lorrach.
Part of the lands of the Dukes of Zähringen, it became the dowry of Clementia of Zähringen when she married Henry the Lion, Duke of Saxony, c.1148. He later exchanged it for some land in the Harz with the Hohenstaufen. When the Hohenstaufen fell, Badenweiler came to the Counts of Urach-Freiburg, passing by marriage in 1303 to a Swiss family, called Neuchâtel-Strassburg. It passed later to the Counts of Fürstenberg, who sold it to their Urach-Freiburg kinsmen in 1368.
In 1398 it was mortgaged to the Habsburgs, who had already acquired Breisgau territory from the Urach-Freiburg family in 1368. They were unable to hold on to Badenweiler, because Frederick with the Empty Pockets, the Habsburg holding the western territories, fell foul of the Emperor Sigismund and the Swiss in 1415. Badenweiler consequently returned to the Urach-Freiburg family until 1444, when the last of them, who was ruler of Neuchâtel in Switzerland, gave it to his cousin, the Margrave of Hachberg-Sausenberg, of the family of the Margraves of Baden. When the Hachberg line died out in 1503, the lordship passed to the Margrave of Baden.