gave full sovereignty to the British Dominions. On 19 May, George personally accepted and approved the Letter of Credence of the new U.S. ambassador to Canada, Daniel Calhoun Roper; gave royal assent to nine parliamentary bills; and ratified two international treaties with the Great Seal of Canada. The official royal tour historian, Gustave Lanctot, wrote "the Statute of Westminster had assumed full reality" and George gave a speech emphasising "the free and equal association of the nations of the Commonwealth". The trip was intended to soften the strong isolationist tendencies among the North American public with regard to the developing tensions in Europe. Although the aim of the tour was mainly political, to shore up Atlantic support for the United Kingdom in any future war, the King and Queen were enthusiastically received by the public. The fear that George would be compared unfavourably to his predecessor was dispelled. They visited the 1939 New York World's Fair and stayed with President Franklin D. Roosevelt at the White House and at his private estate at Hyde Park, New York. A strong bond of friendship was forged between Roosevelt and the royal couple during the tour, which had major significance in the relations between the United States and the United Kingdom through the ensuing war years. Second World War Following the German invasion of Poland in September 1939, the United Kingdom and the self-governing Dominions other than Ireland declared war on Nazi Germany. The King and Queen resolved to stay in London, despite German bombing raids. They officially stayed in Buckingham Palace throughout the war, although they usually spent nights at Windsor Castle. The first night of the Blitz on London, on 7 September 1940, killed about one thousand civilians, mostly in the East End. On 13 September, the couple narrowly avoided death when two German bombs exploded in a courtyard at Buckingham Palace while they were there. In defiance, Elizabeth declared: "I am glad we have been bombed. It makes me feel we can look the East End in the face." The royal family were portrayed as sharing the same dangers and deprivations as the rest of the country. They were subject to British rationing restrictions, and U.S. First Lady Eleanor Roosevelt remarked on the rationed food served and the limited bathwater that was permitted during a stay at the unheated and boarded-up Palace. In August 1942, the King's brother, the Duke