Wahhabism is a Salafi revivalist movement within Sunni Islam named after the 18th-century Hanbali scholar Muhammad ibn Abd al-Wahhab. It was initially established in the central Arabian region of Najd and later spread to other parts of the Arabian Peninsula, and was the official policy of Saudi Arabia until 2022. Despite being founded on the principles of Sunni Islam, the Hanbalite scholars Ibn Taymiyya and Ibn al-Qayyim in particular, Wahhabism may also refer to doctrinal differences distinct from other forms of Sunni Islam. Non-Wahhabi Sunnis also have compared Wahhabism to the belief of the Kharijites and loyalist monarchism. In 2013, a report commissioned by the European Parliament identified Wahhabism as the main source of global terrorism.