Who Is Iran Supreme Leader Ayatollah Ali Khamenei? Cause Of Death, Ideologies And A Quick Look At His 37-Year Reign

Ayatollah Ali Khamenei, Iran's supreme leader, has been killed in a joint US and Israeli air strike on his Tehran compound. The 86-year-old cleric died on 28 February 2026 amid the large-scale operation targeting Iran's leadership, Iranian state media confirmed shortly afterwards with a 40-day mourning period declared.

His death brings to a close a 37-year reign that saw the Islamic Republic become a formidable regional force while maintaining iron-fisted theocratic control at home.

Who was Ayatollah Ali Khamenei?

Born 19 April 1939 in Mashhad, the second of eight children to a religious family, Khamenei became a Shia cleric and opposed the shah, enduring several imprisonments. After the 1979 revolution he served as president from 1981 to 1989.

When Ayatollah Ruhollah Khomeini died, the assembly of experts chose him as supreme leader in June 1989. 'I'm not qualified to be supreme leader. It's not the proper place for me,' he reportedly said beforehand. He survived a 1981 assassination attempt that paralysed his right arm. Khamenei soon exercised absolute authority over state affairs, including the powerful Islamic Revolutionary Guard Corps.

He was the longest-serving head of state in the Middle East when he died. Early in his tenure he focused on rebuilding after the Iran-Iraq war and strengthening institutions to ensure the revolution's survival. By the new millennium reformist challenges had been sidelined.

Ideologies that Defined his Rule

At the heart of Khamenei's vision was velayat-e faqih, the guardianship of the Islamic jurist, granting the supreme leader ultimate oversight. He harboured profound distrust of the West, invoking the idea of westoxification to portray foreign powers as existential threats seeking regime change through sanctions or military means.

This drove his cultivation of the axis of resistance, backing groups such as Hezbollah, Hamas and the Houthis to challenge Israel and the United States across the Middle East.

Khamenei labelled strikes against Israel logical, just and internationally legal. He famously predicted that Israel will not exist in 25 years. The nuclear programme was framed as civilian, supported by a fatwa against weapons of mass destruction.

He showed heroic flexibility in endorsing the 2015 JCPOA deal but permitted gradual breaches following the US exit in 2018. At home, unrest was dismissed as foreign-orchestrated, justifying severe repression to safeguard Islamic governance.

A Quick Look at His 37-Year Reign

Khamenei assumed power on 4 June 1989 and ruled until last week. He expanded Iran's regional reach through proxies in Syria, Yemen and Gaza while the Islamic Revolutionary Guard Corps grew in economic and military influence. Charitable foundations under his control amassed tens of billions in assets amid widespread corruption claims.

Successive protests faced brutal responses, from the 2009 Green Movement to the 2019 killings of 1,500 demonstrators, the 2022 Woman, Life, Freedom movement with over 500 deaths and the 2025 economic unrest. His nuclear ambitions endured despite 2025 bombings. Alliances with Russia and China strengthened, including drone supplies for the Ukraine conflict. The reign concluded with the strikes that claimed his life.

As a reel on the verified Instagram account of Al Jazeera noted, his death has left a vacuum at the top of Iran's complex power structure. Iranian state media hailed him as a martyr on Sunday.

The assembly of experts must now select a successor amid heightened regional instability.