Declassified British/US documents, detailed in a 2023 Declassified UK investigation drawing on Foreign Office files and the CIA’s own 1954 history of Operation Ajax (also known as Operation Boot), show that MI6/the CIA orchestrated the overthrow of Iran’s democratically elected Prime Minister Mohammad Mosaddegh after he nationalised the Anglo-Iranian Oil Company (now BP).
British officials explicitly called for “a non-communist coup d’état” to install “a dictator” who would reverse nationalisation and protect UK oil revenues, with Ambassador Sir Francis Shepherd stating the need for an authoritarian regime to “settle the oil question on reasonable terms.” The coup succeeded on 19 August 1953, restoring the Shah and paving the way for a new oil consortium granting Britain and the US 40% each.
This is according to:
— National Security Archive (George Washington University) – Comprehensive sets of declassified CIA and State Department files: (1) 2013 CIA release confirming role (2) 2017 FRUS retrospective volume
— U.S. State Department – Foreign Relations of the United States (FRUS) 1951–1954 Iran volume: (full retrospective edition with planning and implementation docs)
— CIA FOIA Electronic Reading Room – Key histories including “The Battle for Iran” and internal accounts: (direct PDF of one major history)