The Obama's had afternoon tea with Queen Elizabeth, Wednesday.
Obama is the 11th U.S. president to meet the Queen during her 57-year reign. She was only a princess in 1951 when she met a U.S. president for the first time-- Harry Truman.
Queen Elizabeth has met with every president since then with the exception of Lyndon Johnson. Johnson never visited England during the Vietnam era, and the Queen's pregnancies kept her from traveling.
She did share a bond with President Reagan. They enjoyed riding horses together.
It's also tradition for presidents to bring gifts to the Queen.
The Obamas gave her an inscribed Ipod loaded with video and pictures from the Queen's 2007 visit to Jamestown and Williamsburg, Va.