Commonwealth and Protectorate, The, the republican government in England from the beheading of Charles I in 1649 to the restoration of the monarchy under Charles II in 1660. In 1648, during the Great Rebellion, royalist forces were soundly defeated at Preston. Later that year Parliament was purged of all Presbyterians, who favored negotiating with Charles I and retaining the monarchy. Only Independent Puritans, who favored the authority of Parliament over that of the king, were left as members. (This event is referred to as Pride's Purge, named after Colonel Thomas Pride, commander of the troops that barred the Presbyterians.) The remaining members of Parliament made up what came to be called the Rump Parliament.

Shortly after Charles I was beheaded in January, 1649, The Rump Parliament abolished the House of Lords and the monarchy and established the Commonwealth, which was led by Oliver Cromwell. The first task of Cromwell and his army, in 1649 and 1650, was to put down rebellion in Ireland and Scotland. In 1651 Cromwell defeated a Royalist army under Charles II, who then escaped to France. From 1652 to 1654, England and the Netherlands were engaged in a war provoked by England's first Navigation Act (1651), which had been directed against the Dutch sea trade.

The Rump Parliament, meanwhile, had come into conflict with the army, and in April, 1653, Cromwell dissolved it. The succeeding parliament, called Barebones Parliament (after one of its members), sat for only five months before dissolving itself. Cromwell's officers then drew up the Instrument of Government (December, 1653), a written constitution that created the position of Lord Protector of England and provided for an advisory council and a parliament. The latter provisions were largely ignored and Cromwell, who became Lord Protector, ruled as a virtual dictator.

After Cromwell's death in 1658, his son Richard became Protector, but he soon resigned. General George Monk then took control and reconvened the Long Parliament, paving the way for the return of Charles II. With the restoration of Charles to the throne, all legislation of the Commonwealth and Protectorate period was declared invalid.