Anna an the King of Siam is a 1944 book by Margaret Landon, a play and a 1946 movie directed by John Cromwell. Based on the diaries of Anna Leonowens, a British governess in the Royal Court of Siam (now modern Thailand) during the 1860s, the story mainly concerns the culture clash of the Imperialist Victorian values of the British Empire with the autocratic rule of Siam's King Mongkut. The successful film starred Rex Harrison as the king and Irene Dunne as Anna.