The Protectorate in English history refers specifically to the English government of 1653 to 1659 under the direct control of Oliver Cromwell, who assumed the title of Lord Protector of the newly declared Commonwealth of England (later the Commonwealth of England, Scotland, and Ireland). The Protectorate occurred after the military dismissal of the Rump Parliament, which itself was replaced with a military appointed Barebones Parliament (July-December 1653) to craft a Constitution for England. This plan failed.
Subsequently, the Protectorate was established by the passage of "An Act declaring England to be a Commonwealth" by Parliament, and operated within the lines of a constitutional document entitled the Instrument of Government, which had been drawn up by a group of Cromwell's army officers instead.
Thus, the military Protectorate was established almost as a drifting, default outcome of increasing military power under the New Model Army instead of a plan. This drift is seen since The Protectorate only came into being more than four years after the completion of the English Civil War, the subsequent execution of Charles I, and the successive Rump Parliament and Barebones Parliament.
Although the Protectorate was supposed to divide power between the Lord Protector and an appointed council of state and Parliament, some have branded Cromwellian government as "one of the first experiments in (de facto) military dictatorship" (Abbott). This was said to be accomplished when he used a royalist uprising for a pretext to sweep away the traditional shire governments in 1655, replacing them with military districts administered by army officers.
The Protectorate is associated with the most rigidly enforced puritan legislation. Religious toleration was extended to Jews and most Protestant sects, but not to Anglicans or Roman Catholics.
After Cromwell's death in 1658, the Protectorate devolved upon his son, Richard Cromwell, who was unable to control the army and resigned in May, 1659. After a chaotic interregnum, the Restoration of the monarchy was effected in May 1660, largely through the initiative of General George Monck.