British Democratization
A history of democratization in England, Wales, and Scotland, plus recent history of Northern Ireland.
Note that there is a separate page for Ireland.
Constitutional Monarchy
There is no formal constitutionality to the English monarchy. The current state was achieved through centuries of minor constitutional adjustments. See also the monarchic history of how the separate kingdoms of England, Scotland, and Ireland were bound together into a single United Kingdom.
In 1215, English nobility forced John to agree to the terms of the Magna Carta. This proto-constitution limited royal powers. (Note that this is technically just the kingdom of England.)
The Statute of Monopolies in 1624 disallowed domestic royal monopolies, although royal charters for international companies continued. A chief example being the Royal African Company (RAC), to which Charles II chartered a monopoly on slave trade, with James, Prince of Wales as the governor and primary shareholder. In 1689, RAC seized the cargo belonging to Jeffrey Nightingale, an 'interloper' who attempted to trade monopolized goods. He sued for illegal seizure in the court of king’s bench. In the case of Nightingale v. Bridges, chief justice John Holt ruled in favor of the plaintiff, that the monopoly was created by royal prerogative rather than Parliamentary statute, so the monopoly and the seizure were illegal. This established precedent that royal monopolies were also disallowed for international commerce.
When the Parliament enthroned William and Mary in 1689, it institutionally assumed the power to depose and raise English kings. (Note that this is technically just a personal union of the kingdoms of England and Ireland.)
Civilian government effectively emerged through the Hanoverian succession. First, Walpole rose to be considered the first prime minister. He and his chosen successor Pelham demonstrated power over George II in both policy-making and appointments to government. Following the loss of the American Revolutionary War, the Watson-Wentworth government saw a complete shuffle of government members. Shortly after, the Fox-North coalition formed a government against the will of George III.
Note that civilian here does not imply democratically elected. The Parliament is composed of an elected House of Commons and an ennobled House of Lords. There is only a norm, established in 1963, barring a lord from being prime minister. Furthermore, many 'elected' seats were pocket boroughs in which there was factually no election. This continued until the Representation of the People Act in 1867 (a.k.a. the Reform Act).