Battle of the St. Lawrence

May – October 1942, Gulf of St. Lawrence and the St. Lawrence River, Canada

German success; the St. Lawrence closed to ocean shipping

On 12 May 1942 U-553 sank two freighters in the mouth of the St. Lawrence River, the first ships sunk by the enemy in Canada's inland waters. More U-boats followed through the summer, attacking the small convoys running between Quebec, Sydney and Labrador. In July U-132 sank three ships from one convoy in half an hour. At the end of August U-517 and U-165 came in together. On the night of 7 September U-165 sank the armed yacht Raccoon, which vanished with all hands, and on 11 September U-517 sank the corvette Charlottetown off Cap-Chat; her own depth charges went off as she sank, killing men in the water. U-517 alone sank nine merchant ships, and in October U-69 sank the ferry Caribou in the Cabot Strait; 137 people died. The escorts and aircraft of the Royal Canadian Air Force damaged several U-boats but sank none, and in September the government closed the St. Lawrence to ocean-going shipping, sending it by rail to Halifax and Saint John instead. More than 20 merchant ships and two warships were lost in 1942.