The Safavid dynasty was one of the most significant ruling dynasties of Iran. They ruled one of the greatest Persian empires since the Muslim conquest of Persia and established the Twelver school of Shi'a Islam as the official religion of their empire, marking one of the most important turning points in Muslim history. The Safavids ruled from 1501 to 1722 (experiencing a brief restoration from 1729 to 1736) and at their height, they controlled all of modern Islamic Republic of Iran, Republic of Azerbaijan and Republic of Armenia, most of Iraq, Georgia, Afghanistan, and the Caucasus, as well as parts of Pakistan, Turkmenistan and Turkey. Safavid Iran was one of the Islamic 'gunpowder empires', along with its neighbours, the Ottoman and Mughal empires.