One of the challenges of understanding the consequences of Brexit is the apparent lack of precedent for such an event. But this pre-supposes that only the recent past is relevant. If instead we use the full sweep of history, then we can find the obvious precedent of the English Reformation that started in 1534. King Henry VIII passed the Acts of Supremacy making him “supreme head in earth of the Church of England” and repealing any “usage, custom, foreign laws, foreign authority”. The foreign authority, of course, was the Pope and the Roman Catholic Church. At the time, church law was ultimately under the jurisdiction of Rome. Church taxes were also paid directly to Rome.
We all know that this break from Rome was not theological rather Henry VIII wanted his marriage to Catherine of Aragon to be annulled by the Pope (she had not produced a male heir). He argued that marrying the widow of his brother was “blighted in the eyes of God”. The problem was that he had received a special dispensation from the Pope for the marriage to happen in the first place. Canon Law prevented the Pope from making an exception to an exception. So began England’s break from Rome.
This did not mean things suddenly turned rosy. Indeed, Henry VIII consolidated power in the monarch, removing many of the checks and balances of civil society. He introduced the Dissolution of the Monasteries in 1536 which saw Church lands (one-fifth to one-third of all the land of England) seized by the Monarch and sold to the wealthy to help buttress support for the King. As the Church was often the main provider of income to the poor, many parts of the country, notably the North, rose up in protest. Needless to say these were heavily suppressed.
After Henry’s death in 1547, his son Edward VI took a more theological path and attempted to impose Protestantism on the country. This saw various rebellions across the country. Moreover, after his death in in 1553 when the Catholic Mary I (one of Henry VIII’s daughters) became Queen, she started to repeal much of the Reformation legislation and tried to achieve a reunion with Rome. But Rome was not as forthcoming as before; the Pope wanted a resolution to the confiscation of its property. Mary also had to produce a male heir to prevent her Protestant half-sister Elizabeth returning the country to Protestantism. It was not to be and she died childless in 1558. Elizabeth attempted to be less hard-line than Edward VI, but was not able to prevent the foundations being set for the English Civil War (1642-1651) after her death.
So the “Brexit” of 1534 was far from straightforward, and nor did it stop conflict within the country. As for the economic consequences, GDP per capita barely changed for one hundred years after before falling sharply during the Civil War. It took colonial expansion, notably to India, and later in the industrial revolution in the 1700s for growth to really pick up in England.