It began with Henry VIII and his counsellors deciding that the church courts should not deal with cases of civil law. In the Middle Ages the church courts were the only form of objective justice and all of Europe accepted that the clerks and justices were also usually high ranking clergy. By the time of the Tudors an increasing number of lay men were being trained in law and the Tudor regime decided that matters of civil law should not be decided by ecclesiastical courts. In other words, they started gradually and incrementally to enforce a doctrine of separation of church and state.
The history of the time period is often simplified as “Jolly old Henry VIII was a bit of a lad and wanted to marry his pretty little mistress Anne Boleyn. The Pope was a dull old spoil sport and blocked it so Henry VIII did what any good, red blooded Englishman would do–told the Pope to get off his island.” Not quite. Read more.