After a US-Israeli strike killed Iran’s Ali Khamenei, the war on Iran escalates, and the Islamic Republic faces a critical moment. Mojtaba Khamenei has been elected supreme leader, marking a rare and controversial succession. This explainer breaks down how Iran’s power structure was built after the 1979 Islamic revolution led by Ayatollah Ruhollah Khomeini, and how Ali Khamenei transformed that revolution into a complex political and security structure.

We examine how the supreme leader sits above all institutions in Iran, shaping decisions across government, the military, and the Islamic Revolutionary Guard Corps, and how this system is designed to endure beyond any single leader. As Mojtaba Khamenei takes power, questions grow over how Iran will be governed, how the IRGC will influence decision-making, and whether the system Ali Khamenei built can withstand both internal pressure and external conflict.

From Ali Khamenei to Mojtaba Khamenei, this is the story of Iran’s supreme leader, the system behind power in Iran, and what comes next.