20th and 21st centuries
During World War II, two conferences were held in Quebec City. The first one was held in 1943 with Franklin Delano Roosevelt (the United States' president),Winston Churchill (the United Kingdom's prime minister), William Lyon Mackenzie King (Canada's prime minister) and T.V. Soong (China's minister of foreign affairs).
The second one was held in 1944, and was attended by Churchill and Roosevelt. They took place in the buildings of the Citadelle and of nearby Château Frontenac. A large part of the D-Day Landings plans were made during those meetings.