The Yugoslav Front of the Second World War, also known as the Yugoslav People's Liberation War, is fought in occupied Yugoslavia from 1941 to 1945 between the Yugoslav resistance forces, primarily the Yugoslav Partisans, and the Axis powers.The Yugoslav resistance forces are initially divided into two guerrilla armies: the communist-led Yugoslav Partisans, and the royalist Chetnik movement (known officially as the Yugoslav Army in the Fatherland), while the latter increasingly collaborates with the Axis and loses its international recognition as a resistance force.

After a brief initial period of cooperation, the two factions quickly start fighting against each-other.

Gradually, the Chetniks end up primarily fighting the Partisans instead of the occupation forces, and start cooperating with the Axis in their struggle to destroy Tito's forces, receiving increasing amounts of logistical assistance (in particular, from Italy).