England is one of a very small number of places with a church established by law whose population has largely stopped belonging to it. The Church of England's senior bishops sit in the House of Lords by right, the monarch is its supreme governor, and the coronation remains a religious service conducted by the archbishop of Canterbury with an anointing at its centre. Parish churches carry legal duties toward everyone resident in the parish, whether or not those people attend anything.
Against that stands a change in the returned figures without precedent in the modern period. In the 2021 census for England and Wales, for the first time since the religion question was introduced, fewer than half of respondents described themselves as Christian, and a little over a third recorded no religion. The largest minority faiths, Islam, Hinduism and Sikhism, are concentrated in particular cities and boroughs rather than spread evenly, so a national percentage and a local one can differ enormously, and the same census that shows national decline shows dense religious life in specific places.
The distance between the legal position and those figures is the live argument. Defenders of establishment describe it as a civic arrangement that keeps a place for religion in public life rather than a claim about what most people believe. Critics read the same arrangement as a privilege no longer matched by numbers. Disestablishment has been proposed repeatedly and carried out nowhere in England, although it happened in Ireland in 1871 and in Wales in 1920, and both cases are precedents the argument keeps returning to.