The Moscow Kremlin is the heart of the Russian state, a fortress whose blood-red walls have witnessed more than eight hundred years of political drama and extraordinary violence. It has been the seat of a priestly monarchy, a worldly church and the Soviet Union; it has served as a crossroads for diplomacy, trade, and espionage; it has survived earthquakes, devastating fires, and at least three revolutions. Its very name is a byword for enduring power. From Ivan the Terrible to Vladimir Putin, generations of Russian leaders have sought to use the Kremlin to legitimize their vision of statehood.