Queen Elizabeth II Has Met 12 U.S. Presidents

Queen Elizabeth, who has reigned over England longer than President Obama has been alive, has met with 12 U.S. presidents. Obama was the most recent; he and the first lady made a two-day state visit to Buckingham Palace in April 2009. Here the first couple greets the queen for a dinner at the Winfield House in London, May 25, 2011. (Jewel Samad/AFP/Getty Images)