The ‘self-denying Ordinance’ helped to stop MP’s who didn’t want to defeat the king, hindering such a thing, because they were the people who made up some the officers on the Parliamentarian side. It was passed in 1645 saying that no member of the Lords or the House of Commons could be an army officer. Oliver Cromwell was the only exception.
The New Model Army Ordinance was passed on 19 February 1645, of which Oliver Cromwell officially became the Lieutenant General of Horse in June. Sir Thomas Fairfax (1612 – 1671) was appointed Lord-General and Philip Skippon as Major General. The army was made up of 11 regiments of horse, 12 regiments of foot and 1,000 dragoons, mounted men armed with carbines, in all 22,000 men. It turned their army into an ‘efficient fighting force with a Puritan religious zeal.’ The officers were trained and the soldiers were drilled. The army was well equipped, well fed and paid. Less than half of it was from the existing army and the rest were from London and the eastern countries. Although the King joked about this new army, he was defeated by it in Naseby in the last major battle of the war.
To be in control of London, as Parliament was, was a powerful thing. Parliament had control over London, the customs and the key ports, which meant money. During the years of the war, many supporters of the King would change sides because they found out that Parliamentary soldiers got paid more regularly. This gained more support for Parliament and less for the king. London also had its rich merchants that helped to fund the war
Allies are important in any war. At first, Charles thought other kings in Europe would send troops and money to support him but not a single one did. Charles made peace in Ireland and so his army there came back to fight in England.
In 1643 John Pym made an offer to the Scots. If Parliament won it would set up a Presbyterian Church in England, like the one in Scotland. The Scots had not forgotten how Charles had tried to force them to use the English Prayer book. So they sent 20,000 men to fight on Parliament’s side. They helped defeat the Royalists at Marston Moor in July 1644 and so won control of the North of England. By the time the Scots decided to change sides, the New Model Army was fighting well.
Wars cost money. Charles had many very wealthy supporters and could have funded a short war very easily. But there was no quick victory for him and his supporters so money was becoming a concern.
As well as having the advantage of controlling London, the Parliamentarians were also much more efficient that the Royalists at collecting taxes from the areas they controlled. The King could not afford to raise another army after many of his men were killed at Naseby in 1645
It was not only that Parliament won the First Civil war, but that the Royalists lost. It was not that Parliament had more support than the king, because they didn’t and it was not that Parliament had always been stronger because they hadn’t. The king didn’t take his chance early on, and the Parliamentarian side grew stronger and had good leaders, along with the fact that they had the advantage of support and control over London.