Queen Elizabeth II, currently the world's longest-reigning monarch, met President Donald Trump for an official state visit to the United Kingdom on Monday.
Since 1951, the year before she ascended to the throne, the Queen has met with 12 US presidents and helped facilitate the US and UK's diplomatic relations.
Here's what the queen's relationships and meetings with US presidents have been like from Harry Truman to Donald Trump.
President Donald Trump has landed in the UK for the second time.
She traveled to Washington, DC for the first time to meet President Harry Truman in 1951 when she was a still a princess, and most recently hosted President Donald Trump at Windsor Castle when he visited England last year.
Here's what the queen's relationships and meetings with US presidents have been like, from Harry Truman to Donald Trump. »