Wahhabism, the conservative creed underpinning the ruling ideology of the Saudi dynasty, has become a commonplace word. But whilst many examinations of Wahhabism jump straight from its founder, Muhammad Ibn 'Abd al-Wahhab (1702-91) to the present day, here Tarik K. Firro examines the period in between, after the Ottoman-Saudi War and the subsequent occupation and then partial withdrawal of Ottoman-commanded Egyptian troops in the early nineteenth century. From the Al-Saud's consolidation of their position after Egyptian occupation to their relative decline at the end of the nineteenth century, Firro analyses the 'second Saudi state' in the Nejd. Firro offers insight into the Arabian tribal system and the relationship between the ruling princes, such as Turki Ibn 'Abdallah Ibn Saud and his son Faysal Ibn Turki, with the ulama, such as the al-Shaykh family. In the process he highlights the reasons for the rise and reconsolidation of Wahhabism, as it cemented its claims to be the legitimating touchstone for rulers of the modern Saudi state.