In 1951, the Iranian Parliament, led by Prime Minister Mohammad Mossadegh, voted to nationalize the Anglo-Iranian Oil Company (now BP). Iran wanted control over its own resources and a fairer share of the profits. Britain responded with a worldwide boycott of Iranian oil and a naval blockade, crippling Iran’s economy. The UK (MI6) convinced the US (CIA) that Mossadegh was becoming vulnerable to communist influence. Together, they launched Operation Ajax. The CIA and MI6 used bribery, planted propaganda, and organized staged riots to create chaos and undermine Mossadegh’s government. After a failed first attempt, the coup succeeded in August 1953. Mossadegh was arrested and placed under house arrest for life.
The Shah (Mohammad Reza Pahlavi), who had briefly fled the country, was returned to the throne with absolute power. A new "Consortium" was formed. Instead of the British having a monopoly, the oil was split between British, American, French, and Dutch companies. While the West secured oil for 25 years, the coup destroyed Iran’s burgeoning democracy and convinced many Iranians that the Shah was merely a "Western puppet," fueling the fire for the 1979 Revolution.
Which is why I asked earlier - why are they rioting now? Who has fuelled this fire?