The Committee of Safety was first established on 5 July 1642 to liaise between Westminster and Parliament's armies in the field. It was also responsible for the day-to-day control of military supplies. The committee consisted of five members of the House of Lords: the Earls of Essex, Holland, Northumberland, Pembroke and Viscount Saye and Sele, and ten members of the House of Commons: Nathaniel Fiennes, John Glynn, John Hampden, Denzil Holles, Henry Marten, Sir John Merrick, William Pierrepoint, John Pym, Sir Philip Stapleton, and Sir William Waller.
Disagreements over strategy reduced the Committee's effectiveness and Parliament achieved limited military success under its direction. In February 1644, Parliament secured an alliance with the Scots, and the Committee of Safety was superseded by the Committee for Both Kingdoms for the duration of the First Civil War.
When Presbyterian MPs antagonised the New Model Army, a new Committee of Safety was appointed by Parliament to defend London on 11 July 1647. Composed of Presbyterian members of both Houses, the Committee took control of the Militia Committee and attempted to raise a new army in London with Edward Massie as its general. With the New Model Army advancing towards London, however, neither the citizens nor the Trained Bands supported the Presbyterians. The Common Council of London declared against the levy of soldiers within the City, and Parliament was forced to repudiate the Committee of Safety. The Committee was dissolved and leading Presbyterians fled from the city when the New Model occupied London in August 1647.
The Committee of Safety was revived twice during the political turmoil of 1659.
In May 1659, Richard Cromwell was overthrown and the pre-Protectorate Rump Parliament reinstated. On 7 May, Parliament appointed a seven-member Committee of Safety headed by Lieutenant-General Fleetwood to take over executive authority until the appointment of a new Council of State. Two days later, another four members were appointed, including John Lambert. The Council of State was constituted on 19 May.
In October 1659, Major-General Lambert forcibly dissolved Parliament. Two weeks later the Council of State was also dissolved by order of the Council of Officers. A 23-member Committee of Safety, consisting of army officers and civilians, was appointed and remained in power for nearly two months. The Committee negotiated with representatives sent by General Monck, who opposed the dissolution of Parliament. When Monck threatened to march from Scotland in support of Parliament, Fleetwood restored the Rump Parliament to power in December 1659.
Godfrey Davies, The Restoration of Charles II, 1658-60 (San Marino 1955)
S.R. Gardiner, History of the Great Civil War vol. iii (London 1889)
Ronald Hutton, The British Republic 1649-60 (Basingstoke 2000)
C.V. Wedgwood, The King's War (London 1958)
Journal of the House of Commons, British History Online
Members of the Committee of Safety 1659