In an attempt to win the crown of the Kingdom of Croatia, the Hungarian army crossed the River Drava and invaded Croatian territory, trying to reach the Adriatic coast. A local lord, Petar Svačić, then moved from his residency at Knin castle in an attempt to defend the kingdom from the Hungarians. Petar and his army moved north to meet the advancing Hungarians.

The Battle of Gvozd Mountain took place in the year 1097 and was fought between the army of Petar Svačić and King Coloman I of Hungary. It was a decisive Hungarian victory, which ended the War of the Croatian Succession and served as a turning point in Croatian history.

The outcome of the battle was disastrous for Petar Svačić's army and country because it marked the official end of a native dynasty ruling in Croatia. The winner of the battle, King Coloman of Hungary created a personal union between the kingdoms of Hungary and Croatia (allegedly signing the Pacta conventa). He was then crowned as King of Croatia in the Croatian capital Biograd on the Adriatic coast in 1102. Until the end of the World War I in 1918, the two crowns were united in personal union.