WWI-WWII | Croatia Unbound



Croatia’s future was once again uncertain with the commencement of WW1. After the Austro-Hungarian Empire faced defeat in 1918 after the end of the war, a National Council of Slovenes, Croats, and Serbs (a parliamentary monarchy formed shortly after the war) was formed—an organization quickly reorganized as the Kingdom of Serbs, Croats, and Slovenes.

Croats were hesitant about the new, unifying regime, but they found the threat of Italian invasion (which began in 1918) a greater concern. The diverse populations, thrown so suddenly and poorly together, did not meld well.

Stjepan Radic led the opposition of the new regime, wishing to the transform the concept into a Yugoslavia based on a federal democracy. Radic, th eleader of the Croatian Peasant’s Party, allied with Serbian Svetozar Pribicevic of the Independent Democratic Party. They proved such a threat that Radic and two members of the Peasant’s Party were assassinated in 1928.

In the face of further ethnic violence and civil war, King Aleksander declared a royal dictatorship, dissolved the parliament, put an end to the concept of democratic liberty, and declared the state to the Kingdom of Yugoslavia.


In response to Aleksander’s dictatorship—which essentially instituted a police state—Croat Ante Pavelič founded the Ustaše Croatian Liberation Movement. The Ustaše aimed to establish an independent Croatian state and overthrow Aleksander. Pavelič fled to Italy where he trained his Ustaše troops under the guidance of Mussolini. In 1934, the Ustaše, aided by the benevolent Italian government, assassinated Aleksander in Marseilles.

While the assassination left Yugoslavia vulnerable to growing Nazi influence, Pavelič found himself and his followers imprisoned by Italy.

Yugoslavia’s Prince Pavle eventually aligned with the Axis powers in 1941. However, Pavle was overthrown a mere two days later in the hopes of nullifying the pact. Germany didn’t accept Yugoslavia’s nullification attempts and instead bombed Belgrade on April 6, 1941, invaded Yugoslavia, and installed the Ustaše as the governing power with the support of Italy.

Pavelič, leading the new Independent State of Croatia (NDH), quickly instituted a range of laws meant to persecute any of the regime’s enemies—a long list that included Serbs, Roma, Jews, and political prisoners. Concentration camps were set up, most notoriously at Jasenovac south of Zagreb. It’s unclear how many people died at the concentration camps or throughout Croatia at this time, though it remains clear the Ustaše’s program was carried out with a marked brutality. That being said, it remains a controversial time in Croatian history, and Croats did not unanimously support the Ustaše regime.


Many Croats did not support the Ustaše, and a resistance movement formed almost immediately after German’s 1941 invasion. However, the resistance found itself divided between the pro-Communist Partisans led by Josip Broz ‘Tito’ and pro-Serbian Četniks led by General Draža" Mihailović.

Though the two causes were opposed to the Ustaše, they were equally opposed to one another and found themselves fighting over control for post-war Croatia.

Despite that, Yugoslavia remained Europe’s most effective anti-Axis resistance movement during WWII, and even the internal conflicts kept Axis troops focused on Yugoslavia rather than the Allies.

Tito’s Partisans gained more Allied support over the course of the war, and by 1943 the Partisans controlled much of Croatia with local governments installed. By the end of the war, Tito entered Belgrade while Pavelič fled and the Ustaše fled. You can learn more about Croatia's history on a family-friendly tour.