At the end of World War II in 1945, members of the fascist Croatian ultranationalist and genocidal Ustaše regime from the collapsed Nazi puppet state of the Independent State of Croatia (NDH) fled from the Balkan region to avoid imprisonment and execution at the hands of the Yugoslav Partisans. With the help of Western authorities, who now viewed the fiercely anti-communist stance of the Ustaše favourably in the emerging Cold War, thousands of members of the regime were allowed to migrate to other countries, including Australia.

Despite the post-war Menzies government having the knowledge that the Ustaše were responsible for carrying out genocide against Serbs, Jews and Romani, as well as murdering anti-fascist Croats, they were allowed to obtain citizenship and establish themselves during the 1950s and 60s to fund and organise various terrorist activities within Australia and abroad with the aim of destabilising the Socialist Federal Republic of Yugoslavia.

After a crack-down on Ustaše activities in Australia after 1972, their involvement in large-scale violent acts mostly ceased.

The continued strong infiltration of Ustaša ideology into the Croatian-Australian community assisted significantly to far-right extremism among the Croatian Australians.

Background The Ustaše () (singular: Ustaša) were formed in 1929 as a fascist Croatian ultranationalist group led by Ante Pavelić. The ideology of the movement was a blend of fascism, terrorism and Croatian ultranationalism which called for the creation of a racially "pure" Croatian state and promoted genocide against Serbs, Jews and Roma.

During World War II, Adolf Hitler invaded Yugoslavia and the Nazi puppet state of the Independent State of Croatia (NDH) was established. Pavelić was installed as the Poglavnik or Führer of this state and from 1941 to 1945, this Ustaše regime murdered hundreds of thousands of Serbs, Jews and Roma.

With the German surrender, the end of World War II, and the establishment of socialist Yugoslavia in 1945, the Ustaše movement, along with its state, totally collapsed. Many members of the Ustaše either fled to Italy or were captured, executed or massacred by the Yugoslav Partisans led by Josip Broz Tito. Some of the Ustaše who made it to the Italian displaced persons camps or who were placed under the protection of the Vatican were assisted by Allied authorities in their ability to migrate out of Europe to countries where their vehement anti-Communist stance was deemed to be a potential asset in Cold War geo-politics. This process was dubbed the Ratlines, and Australia became the destination for some of the escaped Ustaše members.

Beginnings of Ustaše in Australia People with Croatian heritage had been migrating to Australia since the late 1800s, and when the Ustaše came to power as a Nazi puppet state in 1941, local Croatian-Australian leaders publicly condemned Ante Pavelić and his fascists. However, as the Ustaše were permitted to enter Australia from the late 1940s, these voices were soon drowned out by the influx of these far-right Nazi collaborators, some of whom were responsible for war-time atrocities.

In 1950, several notable Ustaše figures arrived in Australia as migrants. Amongst these were Djujo Krpan, Ljubomir Vuina, Fabijan Lovoković and Srećko Rover. Krpan was an Ustaša police investigator who was involved in the killing of hundreds of people in the Lika region. ASIO was aware of this but due to his anti-communist credentials, he was given a favourable assessment and given Australian citizenship in 1955.

Vuina was from Sarajevo where he became a pukovnik (colonel) in the Crna Legija (Black Legion), a notorious death squad infamous for their massacres of civilians and the mass deaths at concentration camps which were under their control. Vuina was a founder of the Adelaide Croatia Club in 1950 and Australian authorities estimated that by 1952, around 250 people that had been associated with the Ustaše were members at the club. ASIO later allowed Vuina to set up a newspaper and organise paramilitary training. Vuina obtained citizenship and moved to the Eastern Suburbs of Sydney where he died in 1999. He remained proud of his time in the Crna Legija and believed the unit should be represented at Anzac Day parades. Ironically, the Returned and Services League of Australia has for many years allowed representatives of the genocidal Serbian Nazi-collaborator militia, the Chetniks, to march in Anzac Day parades across the country.

Lovoković was an Ustaše Youth leader who migrated to Sydney in 1950 and re-established Spremnost, a major Ustaša newspaper of the NDH. He also established the Australian branch of the Croatian Liberation Movement (HOP). The HOP was the foremost post-WW2 Ustaše organisation, being founded by the Poglavnik, Ante Pavelić, in 1957. Lovoković regarded himself as the leader of the Ustaše in Australia but took no responsibility for any of its military training or violence. In 1967, Ivica Kokić, a former satnik (captain) in the Ustaša army who had obtained a prominent role in the Australian government service, was appointed as leader of the HOP in Australia.

Srećko Rover was a member of the Gestapo-controlled Ustaše Surveillance Service (UNS) in Sarajevo and led a mobile killing unit that went from village to village arresting and murdering people they judged as enemies. By the end of the war he was in the personal security service of Ante Pavelić and a lieutenant in the Ustaša army. After the collapse of the NDH, he was captured by the Allies and utilised to lead and organise subversive attacks on the communist Partisans as part of the Križari. Most of these missions were a failure and in 1947 Rover was in displaced persons camps in Italy where he became a police officer for the International Refugee Organization. In this role he was able to negotiate his migration to Australia and probably organised for other Ustaše to migrate to this country.

Once in Australia, Rover established himself in Melbourne where he helped form the Melbourne Croatia football club in 1953 and obtained citizenship in 1956. He established the Australian branch of the Croatian National Resistance (HNO) in 1957 which was the more militant post-war wing of the Ustaše that was led from Spain by the notorious Ustaše concentration camp commander Vjekoslav "Maks" Luburić. Again the Australian authorities allowed the Ustaše to organise and openly promote their ideology, an Ustaša float was even permitted to participate in the 1962 Melbourne Moomba parade.

Other significant Ustaše members who migrated to Australia during this early period were Slavko Truhli, Dragutin Sporish and Josip Babić. These men helped establish various front organisations for the Ustaše in Australia including the Croatian Welfare Association and the Australian Croatian Association. ASIO regarded these associations as extremely pro-Ustaša, being little more than recruitment and resource centres for the Ustaše.

In 1961, the Croatian Revolutionary Brotherhood (HRB) was established in Australia by Geza Pašti, Jure Marić and Josip Senić with the later involvement of Father Rocque Romac (aka Stjepan Osvaldi-Toth) and Srećko Rover. This group was an original Australian formation and was integral to the organisation of bombings and insurgencies that occurred both domestically and internationally in the years following.

Organised terrorist activities in the 1960s The anti-communist zeal of the naturalised Ustaše immigrants aligned neatly with the political stance of both the ruling Liberal Party government under Robert Menzies, and ASIO under Charles Spry. This gave the Ustaše a significant degree of freedom and protection to organise major national and international terrorist activities on Australian soil. The extent of this freedom was made clear in April 1963 with the publication of photos of Ustaše training operations centred near Wodonga. The photos of Ustaše men in military fatigues and Ustaše uniforms, armed with Australian Army rifles and sitting on an Australian armoured vehicle, caused a furore which the Liberal Party brushed off as a "picnic". The Spremnost newspaper, however, described it as a 5-day paramilitary training exercise, praising it with an ode entitled "Poem for Terrorism". Ustaše training camps established at Tumbi Umbi, New South Wales. Deszol Saaghy, a former Hungarian member of the Nazi Brandenburger special forces unit and the French Foreign Legion, led the training at Tumbi Umbi.

In July 1963, a group of nine Croatian-Australian men of the HRB were captured conducting covert operations in Yugoslavia with plans to assassinate local officials and raise a rebellion in the north of that country. They were dubbed the Croatian Nine and their assignment was code-named 'Operation Kangaroo'. Two of the men, Stanko Zdrilić and Mirko Fumić, were Australian citizens from Melbourne, while another, Josip Oblak, was the secretary of the Croatian society in Wollongong. All were found to have been trained at Ustaše camps in New South Wales run by the HOP, and all were found guilty in a Yugoslav court, being sentenced to prison terms ranging from 6 to 14 years. Oblak and another man, Ilija Tolić, are believed to have later died while incarcerated.

Further violent Ustaše activities were also being conducted within Australia mostly targeting supporters of a federalist Yugoslavia. In May 1964, HRB member Tomislav Lesić attempted to deliver a suitcase bomb to the Yugoslav consulate in Sydney which prematurely exploded causing the loss of his lower legs and some of his sight. The Ustaše in Melbourne threatened to bomb police stations and shoot officers if they were investigated. In Sydney and Melbourne, houses of perceived communists were either bombed or broken into with occupants being injured and tortured. Various Yugoslav social gatherings were also bombed in places like Geelong and Fitzroy. Leading Ustaša figures in the bombings including Josip Senić and Ambroz Andrić were arrested. When Andrić was placed on trial for bashing a Yugoslav, Srećko Rover supported him in court wearing his Ustaše Gestapo badge.

The bombings continued into 1967, with a large attack on the Sydney Yugoslav consulate, and several attacks on Yugoslav Association meetings, one involving a pen-bomb which resulted in the disfigurement of a boy's face. In 1968, the Ustaše tried to burn down the Sydney Yugoslav consulate, with the Liberal federal treasurer at the time, William McMahon, siding with the arsonists, referring to them as a 'good bunch'.

The Yugoslav government, however, took a more proactive approach to the Ustaše in Australia by utilising their security service, the UDBA, to assassinate leading HRB members Geza Pašti and Josip Senić while they were visiting Europe in 1965 and 1972 respectively.

Increased extremism 1969 to 1973 From 1969 to 1973, the operations of the Ustaše increased dramatically both in their number and in their violence. This coincided with the advent of the Croatian Spring, a widespread movement within Yugoslavia for Croatian autonomy. A total of around 60 attacks were attributed to the Ustaše movement in Australia during this time period and, as in the past, the authorities were still unable or unwilling to halt them. An additional reason for this upsurge was the 1969 assassination in Spain of the HRB's genocidal figurehead, Maks Luburić. More than 60 Luburić supporters demonstrated at the Yugoslav embassy in Canberra following his killing.