A caliphate or khilāfah is a monarchical form of government originated in the 7th century Arabia, whose political identity is based on a claim of succession to the Islamic State of Muhammad and the identification of a monarch called caliph as his heir and successor. The title of caliph, which was the equivalent of titles such as king, tsar, and khan in other parts of the world, had led to many civil wars, sectarian conflicts, and parallel regional caliphates. Historically, the caliphates were polities based on Islam which developed into multi-ethnic trans-national empires. During the medieval period, three major caliphates succeeded each other: the Rashidun Caliphate (632–661), the Umayyad Caliphate (661–750), and the Abbasid Caliphate (750–1517). In the fourth major caliphate, the Ottoman Caliphate, the rulers of the Ottoman Empire claimed caliphal authority from 1517 until the Ottoman caliphate was formally abolished as part of the 1924 secularisation of Turkey. An attempt to preserve the title was tried, with the Sharifian Caliphate, but this caliphate fell quickly, leaving the claim in dormancy.