He stayed in Otočac for a short time before emigrating to Italy in March 1933, where he took the Ustaša oath in the Borgotaro camp on 24 April 1933.

After a general declaration of amnesty in the Kingdom of Yugoslavia, Francetić returned to Croatia in November 1937,[9] but was immediately arrested and exiled to his hometown.

[7] In late 1940 he was arrested in Zagreb due to a congratulatory telegraph to Dr Jozef Tiso, president of the newly formed Slovak Republic, signed by a number of Croat nationalists.

After delivering an inflammatory nationalistic speech at a local school's New Year's celebration in Otočac on 12 January 1941, he escaped to Germany to avoid arrest.

[11] Francetić's Ustashe took control over the local administration by dismissing all civil servants and teachers belonging to the category of "Srbijanci" (Serbs), as well as Jews.

[12] "On 23 July 1941 the headquarters of the NDH Ustasha police sent an order to the heads of all regions, including Francetić, to begin with the arrest and transportation of Jews, Serbs and communists to the Gospić concentration camp.

[13] In August 1941, Ustaša militia under (then Major) Francetić's command were deployed to eastern Herzegovina in order to counter the uprising there.

[14] The 1st Ustaša Regiment (Croatian: Prva Ustaška pukovnija) was raised by Francetić and Ante Vokić in Sarajevo in September 1941.

[20] Commencing on 31 March 1942, and against German wishes, Francetić launched an independent offensive against the Partisans and Chetniks in eastern Bosnia.

The Black Legion quickly captured Drinjača, Vlasenica, Bratunac and Srebrenica from the Partisans and defeated larger Chetnik forces led by Major Jezdimir Dangić.

While flying to Gospić on 22 December, his plane was downed by Yugoslav Partisans near the village of Močile, near Slunj,[28][29] which was a Partisan-held area.

[30] Severely wounded, Francetić was taken to NOVJ General Staff Hospital where Partisan surgeons attempted to save his life in order to exchange him for inmates of Ustaše camps and prisons, but failed.