Rear-Admiral Mark Norman, the deputy commander of the Royal Canadian Navy, said the Battle of the Atlantic is still honoured because of its importance in the war.
"It really was the campaign that kept the war going in Europe," Norman told CBC News. "Without the ability to move important cargo from North America to Europe, the war effort would have either stalled out or might actually have been lost."
A ceremony was held at the National War Memorial on Duckworth Street in downtown St. John's, in concert with other ceremonies held across the country on the first Sunday in May.
Norman said the Battle of the Atlantic resonated particularly in St. John's because of its role throughout the war.
"HMCS Avalon was the base of the entire operation for the northwest Atlantic, with over 25 ships a day coming in and out of this harbour and a massive complement of about 8,000 people, helping to keep that war effort going," Norman said.
The battle came right to Newfoundland's doorstep in 1942, when German U-boats sank four iron ore carriers, killing more than 60.
A wreath was taken to waters off Bell Island, where the battle played out.
"I lived on Bell Island, Lance Cove, and I saw three out of the four boats sunk by German submarines in those years," said resident Charlie Rees.
A moment of silence was held at sea for those who died.
"That war was very close," said Norman. "When you've got U-boats in Conception Bay, I think that's something worth reminding people of."