After Charles' execution, a commonwealth, or republic, was proclaimed. In theory, all power was held by Parliament and a council of state created by it. Oliver Cromwell, however, was the real ruler. Under him, England made great commercial progress, especially in shipping. His foreign policy strengthened England's position in the world.

In 1653 the Protectorate was formed, giving Cromwell dictatorial powers over Parliament. The protectorate did not last long after Cromwell died in 1658. His son Richard, who succeeded him as Lord Protector, was too weak to cope with ambitious generals. Opposition to Puritanism grew. Richard resigned within a year.

In 1660 the Commonwealth Parliament was forced out by an army under George Monk, who had served with the elder Cromwell. Monk reconvened the Parliament of 1648, which then restored the monarchy under Charles II, who reigned 1660-85.