Croatian Military Frontier
Vukassovich was born in 1755. Sources place his birthplace either in Senj or in Sveti Petar, present day village of Bruvno near Gračac. His father was major Petar Vukasović who commanded the fourth Grenz infantry company of the Croatian Military Frontier, headquartered in Sveti Petar. His mother Ana, née Bašić, was also of a Grenz infantry officer family. His birthplace which is in today's Croatia, was initially a nominal part of Kingdom of Croatia within Habsburg Monarchy, but later fully transferred under direct imperial rule as part of the larger Military Frontier. Croatian Military Frontier was placed under the unified control of the Croatian General Command in 1783.