The Sharifian Caliphate (Arabic: خلافة شريفية) was an Arab caliphate proclaimed by the Sharifian rulers of Hejaz in 1924, in lieu of the Ottoman Caliphate.
The idea of the Sharifian Caliphate had been floating around since at least the 15th century. Toward the end of the 19th century, it started to gain importance due to the decline of the Ottoman Empire, which was heavily defeated in the Russo-Turkish War of 1877–1878. There is little evidence, however, that the idea of a Sharifian Caliphate ever gained wide grassroots support in the Middle East or anywhere else for that matter.
The Ottoman sultanate was abolished on 1 November 1922, in the midst of the Turkish War of Independence. The office of caliph, however, was retained for an additional sixteen months, during which it was held by Abdülmecid II. He served as caliph under the patronage of the newly founded Turkish Republic until 3 March 1924, when the Grand National Assembly of Turkey formally abolished the caliphate. Hussein bin Ali then proclaimed himself caliph, basing his claim on his prophetic ancestry and his control of Islam's two holiest mosques, the Masjid al-Haram and Masjid al-Nabawi (collectively known as the Haramayn, Arabic: الحرمين). Possession of the Haramayn was an indispensable condition for any caliph. According to The Times, Mehmed VI, the last Ottoman sultan and penultimate Ottoman caliph, sent a telegraph of support to Hussein after he had proclaimed himself caliph. Nevertheless, King Hussein's caliphate failed to receive wide recognition from the still-colonial Arab world and it was ended when the Hashemite family had to flee the Hejaz region after its capture by the Najdi Ikhwan forces of Ibn Saud (the founder of today's Saudi Arabia) in 1924–1925.