The ruling family of Saudi Arabia. Originally established at Dariyya in Wadi Hanifa, Nejd, in the 15th century, its fortunes grew after 1745 when Muhammad ibn Saud allied himself with the Islamic revivalist Abd al-Wahhab (see wahhabism), who later became the spiritual guide of the family. The first wave of Saudi expansion ended with defeat by Egypt in 1818, but Saudi fortunes revived under Abd al-Aziz ibn Saud (c.1880–1953), who captured Riyadh (1902), and other territories that formed the kingdom of Saudi Arabia in 1932. Abd al-Aziz was succeeded by his sons Saud (1953–64), Faisal ibn Abd al-Aziz (1964–75), Khalid (1975–82), Fahd (1982–2005), Abdullah (2005–15), and Salman (2015– ) as rulers of the richest oil state in the world.