In the latest article from “Beyond the World War II We Know,” a series by The Times that documents lesser-known stories from World War II, James Stavridis, a retired United States Navy admiral and former commander of the United States European Command, looks back on the lives of sailors during the long Battle of the Atlantic.

In the winter of 1994, I was sailing off the coast of Norway in the guided-missile destroyer U.S.S. Barry — my first stint as a ship’s captain. Even given the ship’s 8,000-ton size — vastly larger than the corvettes (small warships) and destroyers of World War II — we were pitching and rolling viciously in the harsh winter seas. As I walked the unstable decks and talked to my sailors standing the long night watches, I told them about the Battle of the Atlantic.

These waters had been the scene of the most difficult and longest naval campaign of the war, with over 100,000 deaths from both sides and close to 5,000 vessels sunk in hundreds of combat encounters. Most of my sailors were in their early 20s, and barely remembered the recently concluded Cold War, let alone the ancient history of World War II. Yet as a destroyer sailor, I knew that you could drop a plumb line from the thousands of North Atlantic voyages of 1939-1945 directly to my young team struggling to keep their dinner rations down in the churning waters half a century later. While the conditions were challenging for us, they were far better than those faced by those brave crews. So what was a day like for those hardy mariners of the turbulent and pivotal Atlantic battle?