The Breisgau (German pronunciation: [ˈbʁaɪ̯sɡaʊ̯] (listen)) is an area in southwest Germany between the Rhine River and the foothills of the Black Forest. Part of the state of Baden-Württemberg, it centers on the city of Freiburg im Breisgau. The district of Breisgau-Hochschwarzwald, which partly consists of the Breisgau, is named after the Black Forest area. Parts of the Breisgau are also situated in the political districts of Freiburg im Breisgau and Emmendingen.
In earlier times, the Breisgau was known as Breisachgau, meaning the county around the town of Breisach on the east bank of the Rhine.
The earliest historically attested inhabitants were Celts. In Roman times, the area was part of the province of Germania Superior, but after the rupture of the limes Germanicus in 260, the area was settled by the Alemanni. It remained a part of Alemannia throughout the Early Middle Ages and was a buffer zone between the central Alemannic lands and Alsace, which was less strongly colonized by the Alemanni.
In the mid-9th century, it was a march-like county guarding the frontier with southern Lotharingia and Alsace. In 859, it was bestowed on Charles the Fat, the son of King Louis I, a sign of its importance. In the 10th century, the Breisgau was a county within the Duchy of Swabia, ruled by the Zähringen family. In the 12th century, they detached themselves from Swabia, establishing the Margraviate of Baden. In the Breisgau, the dukes of Zähringen founded Freiburg, which became their chief city.
From the 13th/14th century to 1797, the area was part of the Vorlande, the area in southwest Germany ruled by the Austrian Habsburgs, but the Breisgau, along with the rest of the Vorlande, was ceded by them to the former Duke of Modena, a relative, as compensation for his loss of his hereditary lands to the French Cisalpine Republic. In 1805, by the Treaty of Pressburg, the area was ceded to the Grand Duchy of Baden.
The Breisgau includes the flat area around river Rhine, the foothills of the Black Forest and the western faces of the southern Black Forest mountains and the Kaiserstuhl hills.
In the south, the Breisgau borders onto the Markgräflerland, in the west onto the Sundgau (Alsace, France), in the east onto the Black Forest, and in the north onto the Ortenau area.
The climate of the Breisgau is warm; in fact, it is the warmest region in Germany. The average annual temperature is 11 degrees Celsius (52 degrees Fahrenheit), the average rainfall is 900 mm (36").
The Breisgau is known for its wine and used for fruit tree orchards and grain.
The biggest city by far in the Breisgau region is Freiburg. Other notable cities and towns are Bad Krozingen, Breisach, Emmendingen, Endingen, Kenzingen, Neuenburg, Staufen and Waldkirch.
A prominent mountain is the Schauinsland (1,284 m).