As Nazi Germany threatened war in Europe, Britain made efforts to strengthen ties with the United States, which included hosting one of the largest foreign pavilions at the 1939 New York World’s Fair. The pavilion’s centerpiece was Lincoln Cathedral’s Magna Carta, making its first appearance outside of Britain. The public presentation of Magna Carta was intended to convey the depth of British and American kinship, both philosophical and historical. “It is felt that Magna Carta symbolizes more than any other document the common origins of British and American democracies,” explained R. A. Mitchell, dean of Lincoln Cathedral. To further the connection, “The Pedigree of George Washington” was displayed near Magna Carta and traced the first president’s descent from King John and nine of the barons that were party to the charter.

When the fair closed in October 1939, the British government extended the document’s stay in the United States to avoid the risk of shipping it home during wartime. In an official ceremony on November 28, 1939, Lord Lothian, the British Ambassador, deposited Magna Carta in the Library of Congress for safekeeping. The Library exhibited it opposite the U.S. Constitution and the Declaration of Independence until April 24, 1940.

After an encore presentation at the World’s Fair, Magna Carta returned to public view at the Library of Congress. When the United States entered World War II in December 1941, the Library evacuated Magna Carta, the Declaration, the Constitution, and other cherished treasures from its collections to Fort Knox, Kentucky. After military officials determined Washington, D.C., was no longer in danger, Magna Carta and the U.S. Charters of Freedom went back on display at the Library on October 1, 1944. Finally, in early 1946, Magna Carta returned to its home in Lincoln Cathedral.