Iran’s Supreme Leader, Ali Khamenei, was killed February 28th in an Israeli airstrike, triggering widespread mourning. Preparations are underway for a multi-day funeral ceremony expected to draw an estimated 20 million Shia Muslim mourners. The loss of Khamenei represents a significant moment for Iran and the wider region. This event is anticipated to have major political ramifications, both domestically and internationally. Details regarding the specifics of the ceremony are still emerging, but it is expected to be a large-scale display of grief and reverence. Security measures are likely to be heightened given the sensitive political climate, and the potential for unrest. The death of Khamenei leaves a power vacuum within the Iranian theocracy.