Francetić was born in Otočac on July 3, 1912. After gymnasium (high school) he went to study law at the University of Zagreb, were he joined the Ustaša movement. Soon after, he was exiled from Zagreb for five years as a result of his anti-Yugoslav political activities. He stayed in Otočac for a short time before emigrating to Italy in March 1933. He took the Ustaša oath in the Borgotaro camp on April 24, 1933, and then spent the following four years in Austria, Italy and Hungary. In Hungary he joined to the Ustashe terrorist group camp at Jankapuszta, under new, conspirative name 'Laszlo'.