Serbs and Roma being gathered before deportation to Kozara and Jasenovac concentration camps (Photo: United States Holocaust Memorial Museum)
Following the invasion of Germany and its allies on Yugoslavia, on April 10, 1940, the Independent State of Croatia (abbreviated NDH) was proclaimed. This puppet state was led by the Ustaša regime, whose leader was Ante Pavelić, nicknamed Poglavnik. NDH included large parts of present-day Croatia, Bosnia and Herzegovina, parts of Serbia and Slovenia, while Dalmatia, Istria, Međimurje, and parts of Baranja were exempted and annexed to Italy and Hungary. Although the country was nominally a kingdom and Prince Amione, Duke of Spoleto was elected as king Tomislav II, Pavelic had the real power in the country, and he, in turn, obeyed the wishes of Germany and Italy that brought him to power. The rump state survived formally until the very end of the war, although the first partisan resistance movements were established as early as 1941, and much of the country, especially the rural parts, was under their control.
The Ustaša, fully known as the Croatian Revolutionary Movement, based much of their ideology on Nazi racial laws. Relying on “German theory” about the non-Slavic origins of Croats, they labeled Jews, Roma, and other Slavs (especially Serbs) as sub-humans, which created the basis for the persecution and imprisonment of thousands of individuals. Political opponents of the regime, communists, anti-fascists, and dissidents were also persecuted, while initially Bosniaks were considered to be Islamized Croats. Ministers in the Pavelic government made it clear that the the regime aimed to create an “ethnically pure” Croatian state and that “undesirable elements” should be removed, deported or forcibly assimilated, if possible. The Ustaša regime became known for its thoroughness and brutality, which displeased even senior Nazi officers.
Soon, concentration camps modeled on those in Germany and Poland began to emerge, first were established in 1941. A total of 22 camps was established, the largest and most notorious being the one in Jasenovac. To estimate the exact number of victims of the Ustaša regime is very disputable. The United States Holocaust Memorial Museum estimates that between 1941 and 1945 between 330,000 and 390,000 Serbs were killed. Of the 39,000 Jews who lived in Croatia before World War II, at least 30,000 were killed. Data for ex-Yugoslavia, however, indicate that 95% of the 68,000 Jews who lived in the Kingdom of Yugoslavia at the beginning of the war, had not welcomed its end.
As for the killed Roma, the data is even more uncertain because the regime did not record data on the individual number of Roma brought to the concentration camps, but only indicated the number of wagons in which they were transported. On 19 May 1942, the military authorities of the NDH sent a circular ordering the round-up of Roma and their surrender to the county authorities, which was followed by mass deportations and executions. According to The Columbia Guide to the Holocaust, about 100,000 Roma lived in the former Yugoslavia before the Second World War, between 26,000 and 90,000 were killed. The pre-war census in Croatia of 1931 lists the number of 14,000 Roma, compared to only 405 in the first post-war census of 1948. Although these are partial figures, because even then many Roma did not declare themselves, it is a good indicator of numerical ration between the pre-war and post-war Roma population.