County of Diez

The Counts of Diez gained prominence in the late twelfth century as strong supporters of the Hohenstaufen dynasty, earning it the nickname "Golden County."

Their seat was at Diez, with their territory extending northeast along the Lahn river to Weilburg, north into the Westerwald, and southeast into the Goldener Grund [de].

Likely due to a matrimonial alliance with the Nürings, Henry II of Diez (r. 1145-1189) inherited significant estates in the Wetterau region.

He accompanied Barbarossa on his Italian Campaigns and engaged in diplomatic missions there, a tradition continued by his son Henry III.

In 1207, Henry III and his brother Gerhard II relinquished control of the Vogtei of Mainz-Kastel to King Philip of Swabia in exchange for imperial immediacy and patronage over the churches in Usingen.

They exercised jurisdiction over the blood court at various locations including Altendiez, Flacht, Hahnstätten, Lindenholzhausen, Dauborn, Niederhadamar (Dehrner Zent), Hundsangen, Nentershausen, Meudt, Salz, Rotzenhahn (Rotenhain), Hoen-Rennerod, Villmar, Schupbach, Panrod, Kirberg, Camberg, Lahr [de], Elsoff, Blessenberg (Frickhofen), and Niederzeuzheim.

The decline of the Counts of Diez commenced toward the close of the thirteenth century with the partition of their domain with the collateral Weilnau line, centered initially at Altweilnau and later at Neuweilnau [de] from 1302 onwards.

In the ensuing years, the weakened Diez line experienced a series of setbacks, losing numerous possessions and privileges.

The remainder of the County, inherited by Adolf's daughter Jutta, passed to her son-in-law, Gottfried VII of Eppstein-Münzenberg.