Simeon Borisov Saxe-Coburg-Gotha (or Sakskoburggotski) (born 16 June 1937) is a Bulgarian politician and former monarch. During his reign as Simeon II, King (or Tsar) of Bulgaria, from 1943 to 1946 he was a minor, the royal authority being exercised over the kingdom on his behalf by a regency. The regents were Simeon's uncle Prince Kiril, General Nikola Mihov and the prime minister, Bogdan Filov. In 1946 the monarchy was abolished as a consequence of a referendum, and Simeon was forced into exile. He returned to his home country in 1996 and formed the political party National Movement for Stability and Progress and became Prime Minister of the Republic of Bulgaria from July 2001 until August 2005. In the next elections he, as a leader of NDSV, took part in a coalition government with the ex-communist party BSP, and in 2009 after NDSV failed to win any seats in the Parliament, he left politics.

Simeon is one of the three last living heads of state from the time of World War II (the others are former King Michael I of Romania and Tenzin Gyatso, 14th Dalai Lama of Tibet), the only living person who has borne the title "Tsar", and one of only two former monarchs in history to have become the head of government through democratic elections (the other is the now-deceased Norodom Sihanouk of Cambodia).

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