Iran’s History: From Cyrus the Great to the 1953 CIA-Backed Coup

In October of 539 BCE, the most powerful king on earth rode into Babylon — and instead of burning it, he freed its slaves. Cyrus the Great recorded the act on a small clay cylinder, a document that would outlast his empire by two and a half millennia and eventually come to rest, with quiet irony, inside a museum in London.

The King Who Let the Slaves Go Free

That moment in Babylon is as good a place as any to begin understanding Iran — not because it is flattering myth, but because it captures something true about the civilization that produced it. The proclamation Cyrus left on that cylinder is often described by historians as among the earliest articulations of human rights in recorded history. It was not the gesture of a conqueror performing mercy for an audience. It was the governing philosophy of an empire that had discovered something Rome would take centuries to learn: that tolerance scales better than terror.

Now hold that image against another: August 1953, Tehran. A democratically elected prime minister is arrested in his pajamas by officers whose operation was planned in Washington and London. Twenty-five centuries separate these two events. Together, they form the frame around everything Iran has been and everything it is still trying to become.

This is a nation of more than 92 million people, the 17th largest country on earth by area, sitting at the precise crossroads where every major Eurasian civilization has collided for five thousand years. The question that haunts its entire modern history is a painful one: how does the country that once ruled the known world end up as a pawn in someone else’s game? The answer requires going back to the beginning.

The Persian Empire: When Iran Ruled Half the World

Around 550 BCE, Cyrus the Great began assembling what would become the largest empire the world had yet seen. Starting from the Iranian plateau, the Achaemenid Empire eventually stretched from the Aegean coast in the west to the Indus River in the east — a swath of territory encompassing dozens of languages, dozens of religions, and populations that had nothing in common except that they now paid taxes to Persepolis.

Darius I, who came to power in 522 BCE, turned that sprawl into something that functioned. He built Persepolis, the empire’s ceremonial heart, with its enormous columned audience halls designed to impress every visiting dignitary with appropriate awe. More practically, he engineered the Royal Road — a roughly 1,700-mile highway running from Sardis in modern Turkey to Susa in southwestern Iran — that allowed royal couriers to cover a journey in seven days that would take an ordinary traveler three months. Armies moved, merchants moved, information moved. The empire had a nervous system.

But the Persian Empire’s real competitive advantage was neither stone nor road. It was the deliberate policy of letting conquered peoples keep their languages, their local rulers, and their gods. Cyrus allowed the Jewish exiles in Babylon to return to Jerusalem and rebuild their temple. Egyptian priests found their cults protected under Persian administration. Local elites across the empire were absorbed into the imperial structure rather than replaced by Persian appointees. This was not sentimentality — it was administrative genius, and it purchased a loyalty that pure force could never sustain.

When Alexander the Great burned Persepolis in 330 BCE — whether in a drunken act of revenge for the Persian sack of Athens or as calculated political symbolism, historians still debate — he destroyed the buildings but could not touch the culture beneath them. Within a single generation, Alexander’s successors were wearing Persian dress, adopting Persian court ceremonial, and marrying into Persian aristocratic families. The pattern that would repeat itself across the next two millennia was already visible: you can conquer Iran, but you cannot replace it.

Empires Within Empires: The Long Middle Centuries

The Parthians reassembled Iranian imperial power from the mid-third century BCE onward. The Sassanid dynasty that followed them, ruling from 224 CE, built a state sophisticated enough to rival Rome — and then Byzantium — for four centuries, in one of history’s longest and most consequential geopolitical standoffs. By the time Arab armies swept across Iran in 651 CE, the Sassanid Empire had already been bled white by decades of grinding warfare with Byzantium. The Arab conquest was swift. The cultural capitulation was not.

Iranians accepted Islam, but they did not dissolve into it. The Persian language survived — a remarkable fact, given that Arabic became the sacred and administrative tongue of the new caliphate across an enormous territory. Within two centuries Persian had re-emerged in a new literary form that would eventually produce Rumi, whose poetry is still read across the world; Avicenna, whose medical encyclopedia remained a standard European university text until the 17th century; and Omar Khayyam, whose contributions to algebra and whose verse outlasted every dynasty that patronized him. Persian culture did not resist Islamic civilization. It became one of its defining pillars, shaping everything from architecture to philosophy to statecraft across the medieval Islamic world.

The Mongol invasions of the 13th century were a different order of catastrophe. Cities like Nishapur, which had been among the Islamic world’s great centers of learning and commerce, were effectively erased. Population losses across the Iranian plateau were staggering — some historians estimate that certain regions lost the majority of their inhabitants. And yet within decades, the Mongol Il-Khanate rulers were converting to Islam, patronizing Persian miniature painting, and commissioning Persian poetry. The pattern held once more: outside force breaks through, and the civilization underneath absorbs the conqueror.

The Safavid dynasty, which ruled from 1501 to 1736, made a decision that would echo through every subsequent century of Iranian history. Shah Ismail I declared Twelver Shia Islam the official state religion, deliberately distinguishing Iran from the Sunni Ottoman Empire to the west and the Sunni Uzbek powers to the northeast. The move was as much strategic as theological — it created a distinctly Iranian religious identity that unified the country’s diverse regions under a single confessional banner while providing a clear ideological frontier against rival powers. The sectarian geography of today’s Middle East was largely drawn in that era, and its consequences have not faded.

The Great Game: When Britain and Russia Started Carving Up Iran

By the 19th century, the Qajar shahs who ruled Iran faced a structural problem that no amount of cultural resilience could solve on its own: two industrial empires were closing in from opposite directions. Britain needed to protect its overland and maritime routes to India, the crown jewel of its empire. Russia was pushing steadily southward, hunting for warm-water ports that would remain navigable through winter. Iran sat precisely between them, and the Qajar court was too factionalized, too financially desperate, and too militarily outmatched to play the two sides effectively against each other.

The result was a series of humiliating concessions. Iran lost large territories to Russia through the treaties of Gulistan in 1813 and Turkmenchay in 1828. Foreign merchants extracted capitulatory privileges that placed them beyond Iranian law. The court borrowed money at ruinous rates and granted commercial monopolies to foreigners to service those debts. When Nasir al-Din Shah sold a tobacco monopoly to a British company in 1890, even Iranian religious scholars — not historically a revolutionary force — joined the popular boycott that forced its cancellation. The line between economic exploitation and political humiliation had disappeared.

The 1907 Anglo-Russian Convention settled the larger strategic question between the two imperial powers, without consulting Iran at all. In a St. Petersburg agreement, British and Russian diplomats divided the country into spheres of influence — a northern Russian zone, a southern British zone, and a nominally neutral strip in the middle. Millions of Iranians woke up in a country that had been partitioned by foreigners who had not needed to set foot inside it to do so. The humiliation was total, and it was remembered.

The following year brought a discovery that would transform the country’s fate. British engineers struck oil in Khuzestan in 1908, and the Anglo-Persian Oil Company — which would eventually be renamed and restructured to become what is now BP — was founded. The financial terms that followed were by any honest measure colonial: Iran received a small royalty on production while Britain used the profits to modernize its Royal Navy. An ancient civilization’s resources were being treated as a dividend owed to London.

World War I completed the degradation. Despite Iran’s declared neutrality, British, Russian, and Ottoman forces all marched across its territory anyway, disrupting agriculture, commandeering food supplies, and triggering a famine that historians estimate killed between one and two million Iranians. It remains one of the 20th century’s least-examined humanitarian disasters, overlooked in part because Iran was not a formal combatant and in part because the imperial powers involved had no incentive to account for it.

The Constitutional Revolution: Iran’s First Experiment with Democracy

Before the coups and the clerical republic, Iran had already tried democracy once — and very nearly made it work. The Constitutional Revolution of 1905 to 1911 produced the first parliament, or Majles, in Iranian history and forced the Qajar shah to accept a written constitution limiting royal power. For a brief period, Iranian liberals, nationalists, clerics, and merchants found common cause in the idea that Iran should govern itself by law rather than by royal whim.

The experiment was strangled by outside interference and internal division. Russia sent troops to suppress the constitutional movement in 1911, shelling the Majles building in Tabriz. Britain, nominally Iran’s protector against Russian encroachment, did little to stop it. The lesson absorbed by a generation of Iranian reformers was the same one that Mosaddegh’s generation would learn four decades later: the great powers supported Iranian self-governance precisely as long as it served their interests and not a moment longer.

That legacy matters for understanding the Islamic Republic. Iran’s experience of secular, Western-aligned modernization — under both the constitutional monarchists and later the Pahlavis — was inseparable from foreign domination and elite corruption. When Khomeini offered an alternative framework, he was not speaking into a vacuum. He was speaking to a century of failure.

The 1953 Coup: Democracy Overthrown in 48 Hours

The most consequential single event in modern Iranian history took less than two days. To understand it, you need to understand Mohammad Mosaddegh — a seventy-year-old politician with a gift for theater and an absolute conviction that Iran’s oil belonged to Iranians. When he nationalized the Anglo-Iranian Oil Company in 1951, he became an instant global symbol of anti-colonial self-determination, appearing on the cover of Time magazine as its Man of the Year. For millions of people across the decolonizing world, he represented the possibility that a small country could simply take back what had been taken from it.

Britain and the United States had a different view. London organized an international oil embargo that strangled Iran’s revenues and lobbied Washington relentlessly for direct action. The Eisenhower administration, driven by Cold War anxieties about Soviet influence and by rather more concrete concerns about oil access, agreed to intervene. The operation — known as Ajax in American records and Boot in British ones — involved CIA and MI6 officers bribing Iranian military commanders, funding mobs to manufacture the appearance of chaos in Tehran’s streets, and coordinating the coup that in August 1953 removed Mosaddegh from office. He was arrested and spent the remainder of his life under house arrest. The Shah, Mohammad Reza Pahlavi, was reinstalled as an absolute ruler backed by Washington.

The lesson Iran’s political class drew from 1953 was not subtle. The West, when forced to choose between oil profits and democratic self-determination in a developing country, would choose oil. Every subsequent generation of Iranian intellectuals, politicians, and clerics has understood this, even when Western analysts have seemed genuinely puzzled by Iranian suspicion of Western intentions. Declassified American government documents released in 2013 formally confirmed what Iranians had believed for sixty years: the CIA was not a peripheral actor in the coup but its primary architect. The confirmation changed nothing on the ground — Iranians had not needed the documents to know — but it closed off the last line of plausible Western deniability.

The Shah’s government that followed built SAVAK, a secret police apparatus trained in part by the CIA and Israel’s Mossad, which imprisoned, tortured, and killed political opponents across the ideological spectrum. The repression was not directed only at leftists or communists — it swept up liberals, nationalists, and eventually the religious opposition that would ultimately overthrow the Shah. By systematically blocking every secular path to political reform, the government inadvertently made the mosque the only available space for organized opposition. The Islamic Revolution of 1979 was, among many other things, the long and predictable consequence of 1953.

Revolution, War, and the Weight of What Came After

When Ayatollah Khomeini returned from exile in February 1979 and a 2,500-year tradition of monarchy collapsed in a matter of weeks, the question Iran had always faced — who gets to define what this place is? — had a new and turbulent answer. The Islamic Republic that emerged replaced a royal autocracy with a clerical one, retaining the authoritarianism while exchanging a secular ideology for a religious one. The constitution it produced was a hybrid document, combining democratic elements like an elected parliament and president with supreme clerical authority vested in the position of the Supreme Leader — a deliberate ambiguity whose tensions have never been resolved.

Barely a year after the revolution, Saddam Hussein’s Iraq invaded Iran in September 1980, launching a war that would last eight years and kill an estimated half-million Iranians. Western powers, including the United States, provided Saddam with battlefield intelligence and looked the other way as Iraq used chemical weapons against Iranian troops and Kurdish civilians — another entry in the archive of grievances that shapes Iranian strategic thinking to this day. The war ended in a ceasefire in 1988 with no territorial changes, enormous human losses on both sides, and an Iranian population that had been asked to sacrifice enormously for a revolution still finding its shape.

The decades since have brought cycles of cautious reform and fierce retrenchment. The reformist presidency of Mohammad Khatami in the late 1990s raised hopes of gradual opening that were systematically blocked by the clerical establishment. The Green Movement of 2009, which erupted after a disputed presidential election, demonstrated the scale of popular frustration with the system before being suppressed. Subsequent waves of protest — in 2019 over fuel prices and in 2022 following the death of Mahsa Amini in morality police custody — showed that the grievances had not diminished. Iran’s government sits atop the world’s second-largest natural gas reserves and fourth-largest oil reserves, yet decades of international sanctions have hollowed out an economy and punished ordinary people for decisions made by a government they did not choose and cannot easily remove.

What the History Actually Explains

Understanding Iran requires holding several things simultaneously that Western political discourse tends to separate. The Islamic Republic is authoritarian and genuinely unpopular with large segments of its own population. It is also the product of a specific history of foreign interference that makes Iranian suspicion of outside actors entirely rational rather than paranoid. The nuclear program, the regional proxy strategy, the anti-Western rhetoric — none of these are fully legible without the context of 1953, the Iran-Iraq War, and the sanctions architecture that followed.

The history of Iran is not a series of defeats. It is a pattern of outside forces breaking through and a civilization bending, absorbing, and re-emerging — shaped by every collision but never fully replaced by any of them. The memory of Cyrus, of the Constitutional Revolution, of Mosaddegh, of the Great Game is not historical nostalgia in Iranian public life. It is live political tissue that operates in every negotiation, every election, every street protest.

The clay cylinder Cyrus left behind in Babylon is held today in the British Museum. Iran has formally requested its return, repeatedly, without success. It is a small administrative matter, almost a footnote in the bilateral relationship. It is also an almost perfect summary of everything still unresolved between this ancient civilization and the world that keeps trying to contain it.