Grožnjan (Italian: Grisignana) is a settlement and municipality in Croatia. It is part of Croatia's Istria County, which takes up most of the Istria peninsula. It is also the only place in Croatia to have an Italian majority. The first mention of Grožnjan dates from 1102. when istrian Marquess Ulrich II and his wife Adelaida granted their land to Patriarch of Aquileia. In this document the fort is called Castrum Grisiniana.
In 1238 Grožnjan was in property of Vicardo I. Pietrapalosa. In 1286 Grožnjan fort was lended to the Aquileian patriarch during war with Venice but changes sided in 1287 and gives Grožnjan to Venice. Vicard’s son Pietro inherited Grožnjan after his father’s death in 1329, and when he died in 1339 it again became patriarch’s property. The patriarch rented it to Friulian noble family de Castello.
In 1354 Grožnjan's new owner became Volrich, or Ulrich, Reifenberg, who in 1358 sold it to Venice for 4,000 ducats in order to pay his debts. Volrich was a son of Deitalm, a descendant of Aquileian patriarch Volcher, and in 1356, during the war between Venice and Hungary, his army, entrenched in Grožnjan, strongly resisted the Hungarian army. Yet it seems that at the same time Volrich negotiated the surrendering of Grožnjan in Venice.