An Islamic state has a form of government based on sharia law. As a term, it has been used to describe various historical polities and theories of governance in the Islamic world. As a translation of the Arabic term dawlah islāmiyyah it refers to a modern notion associated with political Islam (Islamism). Notable examples of historical Islamic states include the state of Medina, established by the Islamic prophet Muhammad, and the Arab caliphate which continued under his successors and the Umayyads.