Hassan Pirnia ( Persian : حسن پیرنیا ‎; 1871 – 20 November 1935), titled Moshir-od-Dowleh, was a prominent politician of 20th-century Iran . He held a total of twenty-four posts during his political career, serving four times as Prime Minister of Iran . He was also a historian, co-founding the Society for the National Heritage of Iran .