This Week on History Happy Hour: Between 1941 and 1945, more than eight hundred shiploads of supplies were delivered to the Soviet Union protected by Allied naval forces. But more than 100 ships were lost in this duty. Each convoy was a battle against the elements, and the Germans - with both sides relying heavily on signals intelligence to intercept and break each other’s codes. The resulting ocean engagements involved aircraft carriers, battleships, cruisers and submarines…and the frightening weather of the Arctic sea.

In this encore episode, we explore this dramatic story with Bletchley Park historian David Kenyon, author of Arctic Convoys: Bletchley Park and the War for the Seas.

David Kenyon is responsible for historical research in support of all public content at Bletchley Park. He also worked for a number of years as an archaeologist, and is one of the UK’s leading experts on the archaeology of the First World War. He has worked on numerous historical television and film projects, including acting as historical advisor to Warhorse in 2010. His books include Bletchley Park and D-Day and Horsemen in No Man’s Land.