Frederick IX of Denmark

Born in 1899 into the House of Glücksburg, Frederik became crown prince at thirteen when his father took the throne in 1912. Trained at the Royal Danish Naval Academy, he married Princess Ingrid of Sweden in 1935; they had three daughters: Margrethe, Benedikte, and Anne-Marie. When Christian X was thrown from a horse in October 1942, Frederik served as regent through the Nazi occupation until 1943. He became king in April 1947 and reigned through twenty-five years of rapid transformation - the welfare state expanded, the economy surged through the 1960s, women flooded into the workforce, and the role of constitutional monarchy had to bend with the times. He died in January 1972, and his eldest daughter succeeded him as Margrethe II.