Chapter 6 provides an overview of the history and development of the Sunnis, emphasizing how adherence to the community (jamāʿa) and the authoritative example (sunna) of the Prophet allowed for a variety of groups to contribute to an ideal of a universal Islam. It shows how the notion of the “rightly guided” caliphs functioned to promote unity across the far-flung ʿAbbāsid Empire, and how the emergence of legal schools sat in creative tension with caliphal pretensions to absolute authority. It shows how a combination of Ahl al-Ḥadīth piety, Murjiʾite notions of faith, as well as Ashʿarite and Māturīdī theology provided the theological basis for a broadly conceived consensus on proper religion. It also shows how Seljuq promotion of the madrasa system allowed for Sunnism to become the dominant communal tendency among Muslims after the sixth/twelfth century. The chapter ends with a discussion of the Karrāmiyya as an example of a group that medieval scholars excluded from the Sunni consensus, and considers why they might have done so.