How were serbians involved in the start of war world II?

Serbians were involved in the start of World War II primarily through the actions of the Kingdom of Yugoslavia, of which Serbia was a significant part. In March 1941, the Yugoslav government signed the Tripartite Pact, aligning with the Axis powers, but following a coup led by pro-Allied forces, the new government withdrew support for the pact. This shift angered Nazi Germany, leading to the invasion of Yugoslavia in April 1941. The conflict escalated as Serbian resistance movements formed, contributing to the broader European conflict.