Anglicanism is a tradition within Christianity comprising churches with historical connections to the Church of England or similar beliefs, worship and church structures. The word Anglican originates in ecclesia anglicana, a medieval Latin phrase dating to at least 1246 that means the English Church. Adherents of Anglicanism are called Anglicans. The great majority of Anglicans are members of churches which are part of the international Anglican Communion. There are, however, a number of churches outside of the Anglican Communion which also consider themselves to be Anglican, most notably those referred to as Continuing Anglican churches.

The faith of Anglicans is founded in the scriptures, the traditions of the apostolic church, the apostolic succession – "historic episcopate" and the early Church Fathers. Anglicanism forms one of the branches of Western Christianity; having definitively declared its independence from the Roman pontiff at the time of the Elizabethan Religious Settlement, in what has been otherwise termed the British monachism. Many of the new Anglican formularies of the mid 16th century corresponded closely to those of contemporary Reformed Protestantism and these reforms in the Church of England were understood by one of those most responsible for them, the then Archbishop of Canterbury, Thomas Cranmer, as navigating a middle way between two of the emerging Protestant traditions, namely Lutheranism and the Calvinism. By the end of the century, the retention in Anglicanism of many traditional liturgical forms and of the episcopate was already seen as unacceptable by those promoting the most developed Protestant principles. In the first half of the 17th century the Church of England and associated episcopal churches in Ireland and in England's American colonies were presented by some Anglican divines as comprising a distinct Christian tradition, with theologies, structures and forms of worship representing a different kind of middle way, or via media, between Reformed Protestantism and Roman Catholicism — a perspective that came to be highly influential in later theories of Anglican identity, and was expressed in the description "Catholic and Reformed". Following the American Revolution, Anglican congregations in the United States and Canada were each reconstituted into autonomous churches with their own bishops and self-governing structures; which, through the expansion of the British Empire and the activity of Christian missions, was adopted as the model for many newly formed churches, especially in Africa, Australasia and the regions of the Pacific. In the 19th century the term Anglicanism was coined to describe the common religious tradition of these churches; as also that of the Scottish Episcopal Church, which, though originating earlier within the Church of Scotland, had come to be recognised as sharing this common identity.