Diez

Diez was an imperial county on the Lahn, ruled from its castle at Diez. In 1337 Count Gerhard VI governed after Nassau-Hadamar’s guardianship over his father’s lands ended in 1332.

Gerhard died fighting Limburg in 1343. The last count, Gerhard VII, died in 1388, and his daughter Jutta brought Diez to Adolf I of Nassau-Siegen. After repeated partitions, the Treaty of Diez divided the county between Nassau-Dillenburg and Trier in 1564. Its lands passed to France in 1795 and the Duchy of Nassau in 1815.