Despite defeat in the First English Civil War, King Charles I of England, Scotland and Ireland retained significant political power. This allowed him to create an alliance with Scots Covenanters and Parliamentarian moderates to restore him to the English throne. The result was the 1648 Second English Civil War, in which he was defeated once again.
Treaty of Newport
In September 1648, at the end of the Second English Civil War, the Long Parliament was concerned with the increasing radicalism in the New Model Army. The Long Parliament began negotiations with King Charles I via the Treaty of Newport intended to bring an end to the hostilities of the English Civil War.
The members wanted to restore the king to power, but wanted to limit the authority he had. Charles I conceded militia power, among other things, but he later admitted that it was only so he could escape.
Negotiations were conducted between September 15, 1648 and November 27, 1648, at Newport, Isle of Wight, on the initial proviso that they would not take longer than forty days (negotiations had effectively broken down by October 27, but continued formally to November). Charles was released on parole from his confinement at Carisbrooke Castle and lodged in Newport.
The New Model Army wanted to prevent Parliament from agreeing on the Treaty of Newport to reinstate King Charles I. While Presbyterian and moderate elements within Parliament were inclined to continue negotiations, the Army was impatient with Charles.
Thomas Fairfax, by issuing a command to Commissary General Ireton, organized a military coup in 1648. Ireton intended to dissolve the Long Parliament but was persuaded to purge it instead. He then ordered Colonel Thomas Pride to prevent the signing of the Treaty of Newport.
Between December 6 and 12, Pride—supported by two regiments—prevented 231 known supporters of the treaty from entering the House, imprisoning 45 for a few days. The remaining free members then became the Rump Parliament.
Pride’s Purge brought Parliament to heel under the direct control of the Army; the remaining Commons (the Rump) then on December 13, 1648, broke off negotiations with the King.
Two days later, the Council of Officers of the New Model Army voted that the King be moved from the Isle of Wight, where he was prisoner, to Windsor, “in order to the bringing of him speedily to justice”. The King was brought from Windsor to London in the middle of December.
The Purge eliminated from Parliament those who backed a negotiated settlement with Charles, which included moderate Independents, as well as Presbyterians.
However, even those who agreed he had to be removed did not necessarily support his execution; this included Fairfax, who refused to take part in his trial, and initially Cromwell, who returned to London from the siege of Pontefract Castle in early December. In return for sparing his life, Cromwell hoped Charles would order the Duke of Ormond to end negotiations with the Irish Confederacy, and prevent a new war in Ireland.
Once it became clear Charles had no intention of doing so, Cromwell became convinced he had to die, stating “we will cut off his head with the crown still on it”.
On January 4, 1649, the House of Commons passed an ordinance to set up a High Court of Justice, to try King Charles I for high treason in the name of the people of England.
The House of Lords rejected it, and as it did not receive Royal Assent, Charles asked at the start of his trial on January 20, in Westminster Hall, “I would know by what power I am called hither. I would know by what authority, I mean lawful authority”, knowing that there was no legal answer under the constitutional arrangements of the time.
When the ordinance to set up a High Court of Justice was rejected by the House of Lords, they declared themselves the supreme power in the state, and proceeded with the trial.
The Purge cleared the way for the execution of Charles in January 1649, and establishment of the Protectorate in 1653; it is considered the only recorded military coup d’état in English history.