County of Isenburg

The states of Isenburg emerged from the Niederlahngau (located in the Rhineland-Palatinate), which partitioned in 1137 into Isenburg-Isenburg and Isenburg-Limburg-Covern.

Today still exist the (Roman Catholic) princes of Isenburg (at Birstein), the (Lutheran) princes of Ysenburg (at Büdingen and Ronneburg) and the (Lutheran) counts of Ysenburg-Philippseich.

Prince Charles of Isenburg-Birstein joined the Confederation and was granted the mediatized Isenburgian Countships of Isenburg-Büdingen, Isenburg-Meerholz, Isenburg-Philippseich, and Isenburg-Wächtersbach.

The Principality continued under the rule of Prince Charles through the Napoleonic era, but was mediatised by Austria in December 1813, at the insistence of King Frederick William III of Prussia, who was angered that Isenburg had raised a regiment for French service by recruiting Prussian deserters and vagabonds.

The lands of the principality were divided between the Grand Duchy of Hesse-Darmstadt and the Electorate of Hesse-Kassel (or Hesse-Cassel).

Isenburg (pink, right) and Lower Isenburg (pink, left) around 1400
Ruins of the Castle at Isenburg (Lower Isenburg)
Büdingen Castle
Castle Ronneburg, Hesse
Birstein Castle
Wächtersbach Castle
Meerholz Castle at Gelnhausen
Philippseich Castle at Dreieich
Coat of Arms of the Principality of Isenburg