This plan had been masterminded by the powerful Elector Albrecht III Achilles of Brandenburg, who married his daughter Elisabeth to Henry's brother Eberhard II.

This would bind the Archbishopric of Mainz tightly to the Margraviate of Brandenburg and to the imperial party, which was led by Albrecht Achilles, and to which Henry's father Ulrich V also belonged.

The plan was directed against the Wittelsbach family, and in particular Elector Palatine Frederick I, who had humiliated Ulrich V in the Battle of Seckenheim in 1462.

In the end, the Elector Palatine won the conflict on a diplomatic level and Henry and the other Württembergs stood empty-handed.

The 1473 Treaty of Urach awarded the county of Montbéliard and the other Württemberg possessions on the left bank of the Rhine to Henry.

Until his death in 1519, Henry and his wife, Eva, were held prisoner on Hohenurach Castle, although they were occasionally allowed to visit Stuttgart.