Iran's Islamic Republic was founded by a revolution that overthrew a hereditary monarch. This week, as the country buries Ayatollah Ali Khamenei, it is confronting the prospect of supreme power passing from father to son.

A billboard spanning a Tehran motorway shows two figures standing together in a garden. One is Ayatollah Ali Khamenei, Iran's supreme leader for thirty-seven years before he was killed in the joint US–Israeli strikes in February. Beside him stands his son, Mojtaba. Above them appears the inscription, "We miss those poetic times." Conceived as a tribute to the late leader, the image has acquired an unmistakable political significance as Iran enters its first transfer of supreme authority since the war.

Four months after Khamenei's death, the Islamic Republic has begun a days-long state funeral expected to draw millions of mourners. His coffin lies in Tehran's Imam Khomeini Grand Mosalla alongside those of his daughter, son-in-law and fourteen-month-old granddaughter, all killed in the same strike. Foreign delegations from Russia, Pakistan, Iraq, Saudi Arabia and Hamas have attended ceremonies, while processions are scheduled to continue through the holy cities of Qom, Najaf and Karbala before Khamenei is buried in his birthplace of Mashhad.

The funeral is carefully choreographed to project continuity after the most consequential military confrontation in the Islamic Republic's history. State television has broadcast vast crowds dressed in black, mourners beating their chests in traditional Shia ceremonies, and banners declaring defiance. Officials have described the funeral as evidence that the institutions of the Islamic Republic remain intact despite war, international pressure and the death of the man who dominated Iranian politics for nearly four decades.

Yet the symbolism extends beyond the funeral itself. The Grand Mosalla was commissioned by Ayatollah Ruhollah Khomeini, whose 1979 revolution overthrew Mohammad Reza Pahlavi and replaced hereditary monarchy with a republic governed by clerical institutions. The revolution's central claim was that political authority would no longer pass through bloodline. Nearly half a century later, the office created to replace the Shah appears set to remain within the same family.

Mojtaba Khamenei has remained almost entirely absent from public life. He has rarely spoken publicly, has seldom been photographed, and has not appeared during the funeral ceremonies despite assuming the position of Supreme Leader in March. His elevation followed his promotion within the clerical hierarchy and formal approval through the Assembly of Experts, preserving the constitutional procedures established after the revolution even as the outcome has invited inevitable comparisons with dynastic succession.

The funeral has also exposed the divisions that continue to define Iranian society. While state media has focused on enormous crowds and official mourning, many Iranians remember Khamenei very differently. One woman whose brother was killed during the anti-government protests earlier this year told NPR, "Even in the Ayatollah's death he still causes us torment." Another, identified only as Fatmeh for fear of retaliation, described arguing constantly with her mother, who regarded Khamenei as inseparable from her faith and was determined to attend the funeral.

Those competing responses reflect the complexity of Khamenei's legacy. To supporters, the funeral represents resilience after war and the preservation of the Islamic Republic. To critics, it marks the passing of a leader whose tenure coincided with intensified repression, expanding power for the Islamic Revolutionary Guard Corps and the violent suppression of domestic dissent.

Whatever judgment history reaches, the images emerging from Tehran this week possess an undeniable historical resonance. A republic established through the overthrow of a king is commemorating its longest-serving ruler while authority passes to his son through the institutions created to prevent hereditary rule. The billboards, the funeral processions and the constitutional formalities all point towards the same conclusion: one of the defining revolutions of the twentieth century has arrived at a succession that would have been instantly recognisable to the monarchy it replaced.