From 1640-60, Royalists were purged from Oxford and a group of Baconians moved into the university behind Parliamentary armies. At the two universities, books were no longer chained to the bookcases. The universities were freed from taxation.
After the civil wars, Cromwell led the country. He was a military, political, and religious leader. He had become a Puritan zealot after a youth of gambling, drinking, debauchery, and rioting. He believed that military success was a reflection of divine favor and he regarded himself as one the few elect preordained for salvation. Those in power in the new Commonwealth tended to explain their regime in terms of popular consent, and the takeover from Charles I as due to his breaking of a contract with the people.
Most people dressed in Puritan fashion. A Puritan's favorite readings were the Old Testament, Epistles of St. Paul, and writings of John Calvin.
Wealth and prosperity steadily increased in spite of the civil wars. During Cromwell's tenure, there was a marked revival of economic prosperity. By the mid-1600s, landlords had been able to shorten their leases so that a lease of twenty-one years was the predominant form of landholding.
Patent protection was given in 1642 for seven years to the inventors of a device for salvaging ships' goods and cannons from the seas. With it they could convert to their own use one half of the items retrieved, the other half going to the Navy and Parliament. Patent protection was given in 1650 to George Manby on his new invention for boiling liquors and making salt with less coal and wood and iron, lead, and copper for fourteen years. Patent protection was given in 1651 for fourteen years to Jeromy Buck for melting iron, lead, tin, copper, brass, and other metals with coal without burning charcoal.
The Merchant Adventurers were incorporated again in 1643 to have a monopoly. It was required to admit into membership for 100 pounds anyone free of London and bred as a merchant, and for 50 pounds any non-inhabitant of London. The penalty for trading for one who was not free of the corporation was forfeiture of his goods.
In 1648, the House of Commons abolished the monarchy and in 1649 the House of Lords. Also in 1649 it declared that England "should thenceforth be governed as a commonwealth and free state by the supreme authority of this nation, the representatives of the people in Parliament." It made a new constitution.
John Milton defended the Commonwealth as superior to the monarchy because it could not deteriorate into tyranny in his books: "First Defense of the People of England" in 1651, and "Second Defense" in 1654. He lauded Cromwell as great in war and great in peace, and exemplifying the principle that "nature appoints that wise men should govern fools".
Thomas Hobbes, the son of a clergyman, and tutor to students, wrote "Leviathan" in 1651 on his theory of sovereignty. Hobbes thought that states are formed as the only alternative to anarchy, barbarism, and war, so that supremacy and unity of a sovereign power is essential to a civilized life and the protection of the citizenry. A sovereign may be a man or body of men as long as his or its authority is generally recognized. There must be a social contract among the citizenry to obey a certain sovereign. To avoid religious conflict, there must be a complete subordination of the church to the state and the religion of a state must be dependent upon its secular sovereign. Hobbes thought that knowledge of the world came through experience and not reason alone. Only matter exists, and everything that happens can be predicted in accordance with exact, scientific laws. He regarded human societies as purely mechanical systems set in motion by human desires. He saw self interest as the mainspring of moral law. Conflicting self interests transformed into a lawful system of agreements. Hobbes opined that all power really originated in the people and that the end of all power was for the people's good.
On the other hand, James Harrington, who wrote "The Commonwealth of Oceana" in 1656, opined that a stable society depended on a direct relationship between the distribution of property and political power; no one with property worth more than 2,000 pounds should be allowed to acquire more and property should be divided among children. A senate of mature property owners were to make and debate the laws while an assembly elected by universal suffrage was to vote on them because "a popular assembly without a senate cannot be wise and a senate without a popular assembly will not be honest". A third of the Senate would turn over every year. John Milton defended the execution of the King in "The Tenure of Kings and Magistrates" in which he maintained that the people may "as often as they shall judge it for the best either to choose him or reject him or depose him, though no tyrant, merely by the liberty and right of freeborn men to be governed as seems to the best". He also wrote in favor of liberty of the press. Ordinary speech found its way into prose writing.