Over 1,000 American airmen were shot down in Serbia during WWII, and both armies helped rescue them. Find out why

In World War II, Americans were sent to a German-occupied area in Serbia to fight. Over 1,000 of these men were shot down by the Germans once over enemy lines. A rescue mission later known as Operation Halyard was created in order to bring these men back home.

The rescue team was organized by Lieutenant George Musulin, along with Master Sergeant Michael Rajacich and Specialist Arthur Jibilian. The rescue team, also known as The Halyard Team, then spent the next month devising rescue plans.

When the rescue team parachuted into the village of Priyani, they noticed that the surviving airmen were spread out into six separate sections. They sought help from a group of Yugoslavian Partisans and Serbian Chetniks, who were known for their conflicting ideologies and were in the middle of a civil war.

This didn't cause a problem because there was no gain that they could receive from turning these Americans over to their German overlords. Their civil war problems were far more important to them, which is why they assisted in the evacuation.

After their careful planning, and avoiding German attacks, the surviving men were evacuated and airlifted to safety. Of the 1,000+ soldiers shot down, 417 were rescued.

(Source)