Operation Weiss
Operation Weiss (German: Unternehmen Weiß), also known as the Fourth Enemy Offensive (Serbo-Croatian: Četvrta neprijateljska ofenziva/ofanziva), was a major Axis offensive launched against the Yugoslav Partisans throughout occupied Yugoslavia during World War II. It was one of the most significant confrontations of World War II in Yugoslavia. The offensive took place in early 1943, between 20 January and mid-to-late March.