The Transcarpathian region of Ukraine is an area known historically as Subcarpathian Rus. Before World War I, Subcarpathian Rus was part of Hungary. In the interwar years it was part of Czechoslovakia.
Hungary seized and annexed Subcarpathian Rus in 1939, in the wake of the dismemberment of Czechoslovakia.
In the first ten days of August 1941, Hungarian authorities expelled about 18,000 Jews from Subcarpathian Rus into German-occupied Ukraine. Hungarian military units rounded the Jews up, loaded them into freight cars, and transported them to Korösmezo (Yasinya), near the prewar Hungarian-Polish border. There they handed the Jews over to German authorities. Many of the Jews were still together as families.
German SS and police units forced the Jews to march from Kolomyja (Kolomyya) to Kamenets-Podolsk (Kam'yanets'-Podil's'kyy) in the western Ukraine, and shot them there. Other than this incident, the Hungarian authorities did not kill Jews in Hungarian-annexed Slovakia or in Subcarpathian Rus before the German occupation. Several thousand of the 42,000 Hungarian Jews who died while serving in Hungarian Labor Battalions were, however, natives of these regions.
On March 19, 1944, the Germans occupied Hungary. They toppled the government of Miklós Kállay and installed a government under Döme Sztójay. Kállay's government had resisted the deportation of the Hungarian Jews. Sztójay's was prepared to move against the Hungarian Jews. By this time, more than 150,000 Jews who had been residents of Czechoslovakia in 1938 lived in Hungary.
Two months after the German occupation, in May 1944, Hungarian authorities systematically deported around 140,000 Jews from southern Slovakia and Subcarpathian Rus to the border of the Government General (central and southern German-occupied Poland). Once they had custody of the Hungarian Jews, German SS and police officials deported them to the Auschwitz-Birkenau killing center. There the SS killed the majority of the deportees in the gas chambers.
A minority of Hungarian Jews arriving in Auschwitz were selected for forced labor. They were used either in the Auschwitz concentration camp complex or transferred west to concentration camps in Germany.
Several thousand Jews managed to escape deportation by hiding in the mountains or fleeing to Romania. Possibly as many as 25,000 Jews from southern Slovakia and Subcarpathian Rus survived the war.
The Germans and their collaborators killed approximately 263,000 Jews who had resided on the territory of the Czechoslovak Republic in 1938.