1921 Persian coup d'état

Government-InsurgentsPersia
Persian Cossack Brigade
Supported by:
United KingdomCommanders and leadersFathollah Khan AkbarReza Khan
Ziaoddin Tabatabaee
Ahmad Amir-Ahmadi

Edmund IronsideStrength 1,500 Persian Cossacks
100 Gendarmerie Casualties and losses Several policemen killed or injured in Tehran during the coup

1921 Iranian coup d'état, known in Iran as 3 Esfand 1299 coup d'état (Persian: کودتای ۳ اسفند ۱۲۹۹ with the Solar Persian date), refers to several major events in Qajar Iran in 1921, which eventually led to the deposition of the Qajar dynasty and the establishment of the Pahlavi dynasty as the ruling house of Iran in 1925.

The events began with a coup by the Persian Cossack Brigade headed by Reza Khan on 22 February 1921. The precise level of British involvement in the coup remains a matter of historical debate, but it is almost certain that Edmund Ironside provided advice to the plotters. With this coup Zia ol Din Tabatabaee took over power and became prime minister. The coup was largely bloodless and faced little resistance. With his expanded forces and the Cossack Brigade, Reza Khan launched successful military actions to eliminate separatist and dissident movements in Tabriz, Mashhad and the Jangalis in Gilan. The campaign against Simko and the Kurds was less successful and lasted well into 1922, though it eventually concluded with Iranian success.