In February 1921, Reza Khan, commander of the Persian Cossack Brigade, staged a coup d'état, becoming the effective ruler of Iran. In 1923, Ahmad Shah went into exile in Europe. Reza Khan induced the Majles to depose Ahmad Shah in October 1925 and to exclude the Qajar dynasty permanently. Reza Khan was subsequently proclaimed monarch as "Reza Shah Pahlavi", reigning from 1925 to 1941.