The First Quebec Conference (codenamed "QUADRANT") was a highly secret military conference held during World War II between the British, Canadian and United States governments. The conference was held in Quebec City, August 17, 1943 – August 24, 1943. It took place at the Citadelle and at the Château Frontenac. The chief representatives were Winston Churchill and Franklin D. Roosevelt, hosted by Canada's prime minister, William Lyon Mackenzie King. Although Churchill suggested that Mackenzie King be involved in all discussions, Roosevelt vetoed the idea. As a result, Mackenzie King's hospitality was almost purely for ceremonial purposes. Joseph Stalin had been invited to join the conference, however he had to decline due to military reasons.