As Axis forces retreated in 1944–45, ethnic German communities that had lived in Hungary and Yugoslavia for generations came under collective suspicion of collaboration. Hungary expelled roughly a quarter-million ethnic Germans in 1946–48 under Allied-sanctioned population transfer, while Yugoslavia's new communist government interned tens of thousands of Vojvodina Germans in camps where many died of hunger, disease and mistreatment before survivors were expelled or fled westward. Total displacement for the two countries combined is estimated at 500,000–720,000. The events largely ended a centuries-old German presence in the Danube basin outside Austria and Germany.
Hungarian and Yugoslav communist-led authorities expelled or forced the flight of ethnic German (Danube Swabian) communities after the collapse of Axis control; in Yugoslavia many were first interned in camps.
Hungary's 1941 census recorded 477,000 people with German as mother tongue but about 720,000 declaring German nationality, a gap that later shaped who was expelled. The Danube Swabians of Yugoslavia, mostly in the Vojvodina and Slavonia, numbered roughly 500,000-540,000 on the eve of the war.
Almost all the deaths are Yugoslav: the West German Schieder Commission (1954-61) counted 69,000 civilian deaths there, of which 48,027 in Yugoslav internment camps such as Rudolfsgnad and Gakovo, and the German Federal Archives (1974) put the figure at 'at least 80,000'. A 1990s enumeration by Danube Swabian expellee organisations, working from named-victim lists, produced a lower total of about 58,000 confirmed dead — well below the West German government's 1958 estimate of 135,800 — and Rüdiger Overmans has criticised the population-balance method behind the higher official figures. For Hungary the Schieder Commission gives about 6,000 deaths, chiefly among the 30,000-35,000 civilians deported to the USSR for forced labour, alongside roughly 180,000-215,000 expelled westward. The gap between figures is methodological: confirmed named deaths versus demographic residuals, with Cold War politics pushing the official West German numbers upward.
The West German Schieder Commission's own categories for Yugoslavia are 5,777 executed by Soviet and Yugoslav forces, 5,683 deportation deaths including 4,500-5,000 in Soviet forced labour, and 48,027 deaths in Yugoslav internment camps, with the 6,000 Hungarian-German deaths attributed to forced labour in the USSR; the German Federal Archives' 1974 report found about 8,000 of some 67,000 deaths in 49 large camps were due to violence and the rest to starvation, disease and maltreatment.
Serbia, Hungary, Austria