any member of the Muslim puritan movement founded by Muḥammad ibn ʿAbd al-Wahhāb in the 18th century in Najd, central Arabia, and adopted in 1744 by the Saʿūdī family.

The political fortunes of the Wahhābī were immediately allied to those of the Saʿūdī dynasty. By the end of the 18th century, they had brought all of Najd under their control, attacked Karbalāʾ, Iraq, a holy city of the Shīʿite branch of Islām, and occupied Mecca and Medina in western Arabia. The Ottoman sultan brought an end to the first Wahhābī empire in 1818, but the sect revived under the leadership of the Saʿūdī Fayṣal I. The empire was then somewhat restored until once again destroyed at the end of the 19th century by the Rashīdīyah of northern Arabia. The activities of Ibn Saʿūd in the 20th century eventually led to the creation of the Kingdom of Saudi Arabia in 1932 and assured the Wahhābī religious and political dominance on the Arabian Peninsula.

Members of the Wahhābī call themselves al-Muwaḥḥidūn, “Unitarians,” a name derived from their emphasis on the absolute oneness of God ( tawhid). They deny all acts implying polytheism, such as visiting tombs and venerating saints, and advocate a return to the original teachings of Islām as incorporated in the Qurʾān and Ḥadīth (traditions of Muḥammad), with condemnation of all innovations (bidʿah). Wahhābī theology and jurisprudence, based, respectively, on the teachings of Ibn Taymīyah and on the legal school of Aḥmad ibn Ḥanbal, stress literal belief in the Qurʿān and Ḥadīth and the establishment of a Muslim state based only on Islāmic law.