The city of Kassa, currently known as Košice in Slovakia, became a focal point of tensions early in World War II when Soviet bombers carried out an aerial raid on June 26, 1941. This attack targeted military installations and transport hubs that were vital to the Hungarian economy. The Soviet Union's military actions were consistent with their larger strategy in Eastern Europe, which involved consolidating power in areas affected by the shifting tides of war. The bombing resulted in significant property damage and civilian casualties, escalating fears among the Hungarian populace and government officials about Soviet ambitions in the region.

In the wake of the bombing, the Hungarian government, led by Prime Minister Pál Teleki, found itself in a precarious position. They needed to balance domestic pressure for a strong response against the Soviets with the country's precarious situation aligned with the Axis powers. The attack effectively galvanized public support for military action, and Hungary's declaration of war on the Soviet Union the following day was seen as a necessary step to defend national sovereignty.

This turn of events was critical not only for Hungary but also for the Axis powers during World War II, as it solidified Hungary’s involvement on the Eastern Front. The alignment with Nazi Germany intensified as it played into the flow of the war, creating an environment of shifting allegiances and military objectives that would shape the conflict’s course. The decision to engage with the Soviet Union out of fear of deeper invasion would force Hungary into a long-standing and costly military commitment, whose ramifications would last well beyond the immediate conflict.