The Act of Uniformity of 1662 required churchmen to use all rites and ceremonies as prescribed in the Book of Common Prayer. It also required episcopal ordination of all ministers of the Church of England—a pronouncement most odious to the Puritans, the faction of the church which had come to dominance during the English Civil War and the Interregnum. Consequently, nearly 2,000 clergymen were "ejected" from the established church for refusing to comply with the provisions of the act, an event referred to as the Great Ejection. The Great Ejection created an abiding public consciousness of non-conformity.
Thereafter, a Nonconformist was any English subject belonging to a non-Anglican church or a non-Christian religion. More broadly, any person who advocated religious liberty was typically called out as Nonconformist. The strict religious tests embodied in the laws of the Clarendon Code and other penal laws excluded a substantial section of English society from public affairs and benefits, including certification of university degrees, for well more than a century and a half. Culturally, in England and Wales, discrimination against Nonconformists endured even longer.
Presbyterians, Congregationalists, Baptists, Calvinists, other "reformed" groups and less organized sects were identified as Nonconformists at the time of the 1662 Act of Uniformity. Following the act, other groups, including Methodists, Unitarians, Quakers, Plymouth Brethren, and the English Moravians were officially labelled as Nonconformists as they became organized.
The term dissenter later came into particular use after the Act of Toleration (1689), which exempted those Nonconformists who had taken oaths of allegiance from being penalized for certain acts, such as for non-attendance to Church of England services.
A religious census in 1851 revealed Nonconformist comprised about half that of the people who attended church services on Sundays. In the larger manufacturing areas, Nonconformists clearly outnumbered members of the Church of England. In Wales in 1850, Nonconformist chapel attendance significantly outnumbered Anglican church attendance. They were based in the fast-growing upwardly mobile urban middle class.