The State Department purchased Blair House in 1942 at the urging of President Franklin Roosevelt when the need for diplomacy grew apace with the American military role in the Second World War.
Previously, guests of the president customarily spent a night in the White House, followed by a hotel or embassy for the remainder of their visit. Winston Churchill’s frequent trips to Washington helped convince President Franklin Roosevelt of the need for official diplomatic housing.
Franklin Roosevelt, Jr., recalls the morning his mother found the prime minister wandering towards the family’s private quarters at 3 a.m., trademark cigar in hand, to rouse the sleeping president for more conversation. He met Eleanor first, however, who firmly persuaded him to wait until breakfast.
The President soon approved the purchase of Blair House—which included the Blair family’s furniture, china and silver—and the President’s Guest House was in business.