During the early part of the Second World War, Halifax was a key Allied port for winning the Battle of the Atlantic. Supplies from Canada and the United States flowed to the British Isles in back-and-forth merchant ship convoys through this Canadian harbour. However, in 1942, the American entry into the war and the fact that British code-breakers were no longer able to decipher German naval radio messages changed the entire naval campaign: North America became vulnerable to German submarine attacks. While on their return voyage against the Eastern seaboard, the aggressive U-boats decided to test Canadian home waters as well.

At the time, Ottawa was inadequately prepared to face this threat. A meagre fleet of fast motor boats, minesweepers and escort vessels were the only safeguards in the Gulf of St. Lawrence. Surprise became the primary advantage for the Germans as the battle began in May 1942. Canadian authorities did not know the exact number and intention of enemy submarines assaulting the shores of Quebec and Newfoundland. By autumn, Allied losses were so bad that the Gulf was closed to all shipping.

Wartime federal censorship and denials of local authorities on the true nature of the submarine attacks meant most Canadians did not understand the scale of this tragedy until the 1970s when secret documents in the National Archives were finally declassified. But even if U-boats first won the battle, they were eventually defeated by naval and air counter-measures hastily implemented in the Maritimes to thwart further damages in the Gulf. In the end, Ottawa was unaware that it had actually secured a strategic victory because the U-boats never came back in strength during the war.

Join the Galt and Dr. Stéphane Guevremont on NOV 05 from 2 to 4 pm for our Café Galt lecture entitled “U Boats Against Canada.” Admission applies.