Muhammad ibn Abd al-Wahhab in the context of "Maddhab"

The first Saudi state (Arabic: الدَّوْلَةُ السُّعُودِيَّةُ الْأُولَىٰ, romanized: ad-dawla as-suʿūdiyya al-ʾūlā), officially the Emirate of Diriyah (Arabic: إمارة الدرعية, romanized: ʾimāra ad-dirʿiyya), was a state that existed between 1744 and 1818, when the emir of a Najdi town called Diriyah, Muhammad I, and the religious leader Muhammad ibn Abd al-Wahhab signed a pact to found a socio-religious reform movement to propagate the Wahhabi religious doctrine under the political leadership of the House of Saud.

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 Taimiyya 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 despite the two belief systems being contradictory to each other.

The Wahhabi movement staunchly denounced rituals related to the veneration of Muslim saints and pilgrimages to their tombs and shrines, which were widespread amongst the people of Najd. Ibn 'Abd al-Wahhab and his followers were highly inspired by the Hanbali scholar Ibn Taymiyya (1263–1328 CE/AH 661–728) who advocated a return to the purity of the first three generations (salaf) to rid Muslims of bid'a (innovation) and regarded his works as core scholarly references in theology. While being influenced by Hanbali school, the movement repudiated taqlid to legal authorities, including oft-cited scholars such as Ibn Taymiyya and Ibn Qayyim (d. 1350 CE/AH 751).

The People of Monotheism may translate several Arabic terms:

• Ahl al-Tawḥīd (Arabic: أهل التوحيد), a name the Druze use for themselves. Literally, "The People of the Unity" or "The Unitarians", from tawḥid, unity (of God).
• al-Muwaḥḥidun (Arabic: الموحدون) is an Arabic term meaning "the monotheists". It has currency as:
  • the Arabic name of the Almohads.
  • the term used by the early followers of the 18th-century Arabian Muwahhidun movement of the reformer Muhammad ibn Abd al-Wahhab to describe themselves
  • a term that adherents of Salafism use to describe themselves.
  • a term that the Druze use to describe themselves.
  • a term that the Alawites use to describe themselves.
• Ahl al-ʿAdl wa t-Tawḥīd, "The People of Justice and Monotheism", a term used by the Mu'tazilis to describe themselves.

The Diriyah pact was an agreement signed between the Emir of Diriyah, Imam Muhammad bin Saud, and Imam Muhammad bin Abdul-Wahhab in the year 1744. The two imams agreed to call for correcting the people's faith from the polytheism, heresies, and superstitions attached to it, by returning to what Muhammad was upon, and carrying out the duty of enjoining what is right and forbidding what is wrong. After the pact, the reform movement began its work, and the Salafist call spread and became widely influential with supporters throughout the Arabian Peninsula and outside it. The pact is considered the basis on which the modern Saudi state was established.

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 Taimiyya 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.

The Wahhabi movement staunchly denounced rituals related to the veneration of Muslim saints and pilgrimages to their tombs and shrines, which were widespread amongst the people of Najd. Ibn 'Abd al-Wahhab and his followers were highly inspired by the Hanbali scholar Ibn Taymiyya (1263–1328 CE/AH 661–728) who advocated a return to the purity of the first three generations (salaf) to rid Muslims of bid'a (innovation) and regarded his works as core scholarly references in theology. While being influenced by Hanbali school, the movement repudiated taqlid to legal authorities, including oft-cited scholars such as Ibn Taymiyya and Ibn Qayyim (d. 1350 CE/AH 751).

Petro-Islam is a neologism used to refer to the international propagation of the extremist and fundamentalist interpretations of Sunni Islam derived from the doctrines of Muhammad ibn Abd al-Wahhab, a Sunni Muslim preacher, scholar, reformer and theologian from Uyaynah in the Najd region of the Arabian Peninsula, eponym of the Islamic revivalist movement known as Wahhabism. This movement has been favored by the Kingdom of Saudi Arabia and the other Arab states of the Persian Gulf.

Its name derives from source of the funding, petroleum exports, that spread it through the Muslim world after the Yom Kippur War. The term is sometimes called "pejorative" or a "nickname".According to Sandra Mackey the term was coined by Fouad Ajami. It has been used by French political scientist Gilles Kepel, Bangladeshi scholar Imtiyaz Ahmed, and Egyptian philosopher Fouad Zakariyya, among others.