Counts of Lenzburg

The Counts of Lenzburg (also Counts of Baden by the early 12th century) were a comital family in the Duchy of Swabia in the 11th and 12th centuries, controlling substantial portions of the pagi of Aargau and Zürichgau.

After the extinction of their male line in 1173, their lands were distributed between the houses of Kyburg, Zähringen and Hohenstaufen. Subsequent Habsburg expansion into former Lenzburg territories were one of several factors that led to the formation of the Old Swiss Confederacy in the late 13th century.