What to know about Iran’s Supreme Leader Ayatollah Ali Khamenei

In one of his final public displays of power, Iran’s Supreme Leader Ayatollah Ali Khamenei unleashed the bloodiest crackdown of his nearly four-decade rule to crush nationwide protests in which people dared to shout “Death to Khamenei.”

Now a U.S. or Israeli military strike has sent Iran spinning into the unknown. The 86-year-old supreme leader is dead, with no designated successor.

Iranian state media confirmed his death early Sunday, hours after President Donald Trump said Khamenei was killed in a major new attack by U.S. and Israeli forces. Trump also urged Iranians to topple the theocracy. As rumors of the death spread, some Tehran residents cheered from rooftops.

Long before the supreme leader’s compound was among the first targets on Saturday, Khamenei had been under growing pressure. In the past year, Trump had directly threatened him, saying he could have killed the Ayatollah if he wanted to, while rejecting an Israeli plan to do just that during last year’s 12-day conflict.

In recent weeks, the supreme leader tried to avert strikes as the U.S. built up its military presence in the region to pressure Tehran over its nuclear program. He warned that if the U.S. struck, a regional war would ensue. Simultaneously, he permitted Iran to enter negotiations with the U.S. over its controversial nuclear program.

The brutal suppression of recent protests, with thousands killed, underscored the threat that popular anger represented to the regime. Years of international sanctions, economic mismanagement, and endemic corruption have devastated Iran’s economy, driving much of the population into poverty.

Israeli and U.S. bombardment during last summer’s 12-day war had already severely damaged Iran’s nuclear program, missile systems, and military capabilities. Iran’s network of regional proxies, including Hamas in Gaza, Hezbollah in Lebanon, and the Houthis in Yemen, has been weakened by Israeli and U.S. attacks since the Gaza conflict began, diminishing Tehran’s influence across the Middle East.

When Khamenei rose to power in 1989, many doubted his authority. A relatively low-level cleric at the time, he lacked the religious credentials of his predecessor, Ayatollah Ruhollah Khomeini, who had led the 1979 Islamic Revolution. Yet Khamenei ruled three times longer than Khomeini and arguably shaped Iran even more dramatically.

He entrenched the system of rule by Shiite Muslim clerics, positioning them atop the hierarchy and establishing parameters that the civilian government, military, and intelligence apparatus had to follow. To hard-liners, Khamenei stood as the unquestionable authority—subordinate only to God.

Simultaneously, Khamenei transformed the paramilitary Revolutionary Guard into the dominant force in military and internal politics. The Guard now controls Iran’s most elite military units and oversees its ballistic missile program. Khamenei granted the Guard extensive autonomy to build a network of businesses and dominate the economy. In return, it became his loyal enforcement mechanism.

The first major challenge to Khamenei’s authority came from the reform movement that gained parliamentary majority and the presidency shortly after he became supreme leader. Reformists advocated for greater power for elected officials—a vision Khamenei and his supporters feared would undermine the Islamic Republic’s foundations.

Khamenei mobilized the clerical establishment, and unelected bodies controlled by religious authorities systematically blocked major reforms and barred reform candidates from elections.

Since then, his regime has crushed multiple waves of popular protest. Massive demonstrations erupted in 2009 over allegations of vote-rigging. Economic protests broke out in 2017 and 2019 under crushing sanctions. In 2022, protests followed the death of Mahsa Amini, who was detained by morality police for improperly wearing her mandatory headscarf.

The most recent demonstrations began in late December in Tehran’s traditional bazaar after the country’s currency, the rial, plummeted to a record low of 1.42 million to the U.S. dollar. Protests rapidly spread nationwide.

“Rioters must be put in their place,” Khamenei declared. When hundreds of thousands took to the streets on January 8 and 9, security forces opened fire on crowds. Activists documented more than 7,000 killed and continued verifying additional deaths. The government acknowledged over 3,000 dead—still higher than any previous crackdown.

By agreeing to nuclear negotiations, Khamenei likely sought to buy time to avert U.S. strikes. However, Iran resisted Washington’s primary demands to halt all nuclear enrichment and surrender its uranium stockpiles.

Officially, a panel of Shiite clerics is responsible for selecting Khamenei’s successor, with multiple names circulated, including his son. Danny Citrinowicz, an Iran expert at Israel’s Institute for National Security Studies, noted that a key lesson Tehran drew from last year’s war was the need to ensure regime continuity if Khamenei died.

“It is possible that Khamenei has indicated a preferred successor behind closed doors,” Citrinowicz said. “However, automatic implementation of a preselected successor will increase internal friction during war.”

The Revolutionary Guard has grown into Iran’s most powerful institution. Khamenei’s death could prompt Guard commanders or the regular military to seize power more overtly, potentially triggering a bloody power struggle for control of this oil-rich nation of 85 million people.