This chapter focuses on Wahhabism during the period of the first Saudi state, as this period provides us with the most influential sources of iconoclastic ideas. The teachings of Ibn ʿAbd al-Wahhab and his disciples constitute the core part of current Salafi thought, appearing in a variety of mutated forms. The purpose of this chapter is twofold. First, it expounds on classical Wahhabi doctrine, as excerpted from early texts. Second, as Wahhabism, or indeed Hanbalism, were not the only strongly iconoclastic trends, this chapter also focuses on other influential movements, especially those of Yemeni, Syrian, Iraqi and Indian traditionalists, with Muhammad al-Shawkani, Ibn al-Amir al-San‘ani, Mahmud Shukri al-Alusi and Siddiq Hasan Khan in the forefront of developments. Finally, the chapter also provides a description of the two waves of destruction committed by Wahhabis after their conquest of the Hijaz, first in the early nineteenth century and then again in the first quarter of the twentieth century.