What happened on December 5 1941?

OPERATION BARBAROSSA!

During World War Two, on the 22 June 1941, Hitler and his German Army attacked Russia as they wanted Russia's land. However Hitler began to get greedy and wanted to take over Moscow as well. Because Germany was against so many countries now, they lost... on the 5th of December 1941.

So to answer your question: On December 5th 1941, Germany lost Operation Barbarossa.