In 1640 Cromwell returned to Parliament when he was elected to represent Cambridge. Cromwell was a strong critic of Charles II and on the outbreak of the Civil War he joined the Parliamentary forces and served under Edward Montagu, Duke of Manchester.
Although Cromwell had no military training, his experience as a large landowner gave him a good knowledge of horses. Cromwell became convinced that if he could produce a well-disciplined army he could defeat Prince Rupert and his Cavaliers. He knew that pikemen, armed with sixteen-foot-long pikes, who stood their ground during a cavalry attack, could do a tremendous amount of damage.
Cromwell also noticed that Prince Rupert's cavalry were not very well disciplined. After they charged the enemy they went in pursuit of individual targets. At the first major battle of the civil war at Edgehill, most of Prince Rupert's cavalrymen did not return to the battlefield until over an hour after the initial charge. By this time the horses were so tired they were unable to mount another attack against the Roundheads.
Cromwell trained his cavalry to keep together after a charge. In this way his men could repeatedly charge the Cavaliers. Cromwell's new cavalry took part in its first major battle at Marston Moor in Yorkshire in July 1644. The king's soldiers were heavily defeated in the battle. Cromwell's soldiers became known as the Ironsides because of the way they cut through the Cavaliers on the battlefield.
At the beginning of the Civil War, Parliament relied on soldiers recruited by large landowners who supported their cause. In February 1645, Parliament decided to form a new army of professional soldiers. This army of 22,000 men became known as the New Model Army. Its commander-in-chief was General Thomas Fairfax, while Cromwell was put in charge of its cavalry.
Members of the New Model Army received proper military training and by the time they went into battle they were very well-disciplined. In the past, people became officers because they came from powerful and wealthy families. In the New Model Army men were promoted when they showed themselves to be good soldiers. For the first time it became possible for working-class men to become army officers. Cromwell thought it was very important that soldiers in the New Model Army believed strongly in what they were fighting for. Where possible he recruited men who, like him, held strong Puritan views and the New Model Army went into battle singing psalms, convinced that God was on their side.
The New Model Army took part in its first major battle just outside the village of Naseby in Northamptonshire on 14 June 1645. The battle began when Prince Rupert led a charge against the left wing of the parliamentary cavalry which scattered and Rupert's men then gave chase.
While this was going on Cromwell launched an attack on the left wing of the royalist cavalry. This was also successful and the royalists that survived the initial charge fled from the battlefield. While some of Cromwell's cavalry gave chase, the majority were ordered to attack the now unprotected flanks of the infantry. Charles I was waiting with 1,200 men in reserve. Instead of ordering them forward to help his infantry he decided to retreat. Without support from the cavalry, the royalist infantry realised their task was impossible and surrendered.
By the time Prince Rupert's cavalry returned to the battlefield the fighting had ended. Rupert's cavalry horses were exhausted after their long chase and were not in a fit state to take on Cromwell's cavalry. Rupert had no option but to ride off in search of Charles I.
The battle was a disaster for the king. About 1,000 of his men had been killed, while another 4,500 of his most experienced men had been taken prisoner. The Parliamentary forces were also able to capture the Royalist baggage train that contained his complete stock of guns and ammunition.
The Battle of Naseby was the turning point in the war. After Naseby, Charles was never able to raise another army strong enough to defeat the parliamentary army in a major battle.
In January 1647, Charles I fled to Scotland where he was captured and handed over to the parliamentary army. Charles was imprisoned in Hampton Court, but in November 1647 he escaped and managed to raise another army. This time Charles was able to persuade the Scots to fight on his side.
In August 1648 Cromwell's parliamentary army defeated the Scots and once again Charles was taken prisoner. Now that Parliament was in control of England its members began to argue amongst themselves. Most Members of Parliament were Presbyterians. These men were willing to share power with the king. Presbyterians also had strong feelings on religion. They disapproved of other puritan groups such as the Anabaptists, Quakers and Congregationalists and wanted them suppressed.
The other major group were called the Independents. They tended to be followers of the religious groups that the Presbyterians wanted to suppress. The Independents argued for a policy of religious toleration. Some Independents also wanted to bring an end to the monarchy.
The Independents had a strong following in the parliamentary army and had the support of Oliver Cromwell. Afraid of their power, Presbyterianmembers of the House of Commons tried to disband the army. The soldiers were furious, especially as Parliament made no effort to pay them the wages that were due to them. The army decided to take action. The Presbyterians were expelled from Parliament. With the Independents now in control, it was decided to put Charles I on trial as a traitor. In 1649 Charles was found guilty and executed outside his Whitehall Palace.
The Independents now passed a series of new laws. The monarchy, the House of Lords and the Anglican church were abolished. Lands owned by the royal family and the church were sold and the money was used to pay the parliamentary soldiers. The Independents also kept their promise regarding religious toleration. People were no longer fined for not attending their local church. However, everyone was still expected to attend some form of religious worship on Sundays.
In August 1649, Cromwell and 12,000 soldiers arrived in Ireland. During the next ten years of bloodshed it is estimated that about a third of the population was either killed or died of starvation. The majority of Roman Catholics who owned land had it taken away from them and were removed to the barren province of Connacht. Catholic boys and girls were shipped to Barbados and sold to the planters as slaves.
The land taken from the Catholics by Cromwell was given to the Protestant soldiers who had taken part in the campaign. Before the rebellion in 1641, Catholics owned 59% of the land in Ireland. By the time Cromwell left in 1650 the proportion had shrunk to 22%.
Although the House of Commons continued to meet, it was Cromwell and his army that controlled England. In December 1653, the army decided that Cromwell should become England's new ruler. Some officers wanted him to become king but he refused and instead took the title Lord Protector of the Commonwealth. However, Cromwell had as much power as kings had in the past. When the House of Commons opposed his policies in 1655, he closed it down.
Cromwell now imposed military rule. England was divided into eleven districts. Each district was run by a Major General. The responsibilities of these Major-Generals included maintaining order, collecting taxes, granting poor relief and imposing Puritan morality. In some districts bear-baiting, cock-fighting, horse-racing and wrestling were banned. Betting and gambling were also forbidden. Large numbers of ale-houses were closed and fines were imposed on people caught swearing. In some districts, the Major-Generals even closed down theatres.
Former members of the Levellers grew disillusioned with the dictatorial policies of Cromwell and in 1655 Edward Sexby, John Wildman and Richard Overton were involved in developing a plot to overthrow the government. The conspiracy was discovered and the men were forced to flee to the Netherlands.
In May 1657 Edward Sexby published, under the pseudonym William Allen, Killing No Murder, a pamphlet that attempted to justify the assassination of Cromwell. The following month he arrived in England to carry out the deed, however, he was arrested and imprisoned in the Tower of London.
In 1658 Cromwell announced that he wanted his son, Richard Cromwell, to replace him as Lord Protector of the Commonwealth. The English army was unhappy with this decision. While they respected Oliver as a skillful military commander, Richard was just a country farmer.
Oliver Cromwell died on 3rd September 1658. His son became Lord Protector but in May 1659, the generals forced him to retire from government. As a result of the Restoration in 1660, Cromwell's body was disinterred from the tomb of kings in Westminster Abbey and was hung from the gallows at Tyburn.