Simeon Borisov Saxe-Coburg-Gotha is a Bulgarian politician who reigned as the last tsar of the Kingdom of Bulgaria as Simeon II from 1943 until 1946. He was six years old when his father Boris III of Bulgaria died in 1943. Royal power was exercised on his behalf by a regency council led by Simeon's uncle Kiril, Prince of Preslav, General Nikola Mihov and prime minister, Bogdan Filov. In 1946 the monarchy was abolished by referendum, and Simeon was forced into exile.

Boris III, originally Boris Klemens Robert Maria Pius Ludwig Stanislaus Xaver, was the Tsar of the Kingdom of Bulgaria from 1918 until his death in 1943.