Just to correct you: the monarch is not the head of the Anglican Church, but the head of the Church of England. There is a distinction. The Church of England (CofE) is a member of the Anglican Communion, which is a predominantly Western Europe conglomerate of around 45 different churches, of which CofE is but one. There will be some confusion as the CofE was (one of, if not) the founding church of the Anglican Communion, and has been referred to as the Anglican Church, but more strictly the CofE should be better referred to as the Anglican Church in England, thus distinguishing it from the Anglican Churches elsewhere. Each has its own governance, head etc. The UK monarch is only the head of the CofE (the Anglican Church in England). The CofE probably only has about c.1 million active worshippers (i.e. church attendance), although possibly 20-30m or so might claim CofE in the census, being the number baptised.