The House of Saud is the ruling royal family of Saudi Arabia. It is composed of the descendants of Muhammad bin Saud, founder of the Emirate of Diriyah, known as the First Saudi state (1744–1818), and his brothers, though the ruling faction of the family is primarily led by the descendants of Ibn Saud, the modern founder of Saudi Arabia. The most influential position of the royal family is the King of Saudi Arabia. King Salman, who reigns currently, chose first his nephew and then his son as the crown prince without consulting the Allegiance Council. The family is estimated to comprise 15,000 members, but the majority of the power and wealth is possessed by a group of about 2,000 of them.

The House of Saud has gone through three phases: the Emirate of Diriyah, the First Saudi State (1744–1818), marked by the expansion of Wahhabism; the Emirate of Nejd, the Second Saudi State (1824–1891), marked with continuous infighting; and the Third Saudi State (1902–present), which evolved into Saudi Arabia in 1932 and now wields considerable influence in the Middle East. The family has had conflicts with the Ottoman Empire, the Sharif of Mecca, the Al Rashid family of Ha'il and their vassal houses in Najd, numerous Islamist groups both inside and outside Saudi Arabia and Shia minority in Saudi Arabia.

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