of the government, with the assistance of a group of English Parliamentary cavalry led by Cromwell. Accession of Charles II Exasperated by the prolonged bloodshed, the New Model Army purged parliament and established the Rump Parliament, which had Charles tried for treason against the English people; he was executed on 30 January 1649, and the republican Commonwealth was created. The Scottish Parliament, which had not been consulted prior to the King's execution, declared his son, also Charles, king of Britain. Before they would permit him to return from exile in the Dutch Republic to take up his crown, they demanded that he first sign both Covenants: recognising the authority of the Kirk in religious matters and that of parliament in civil affairs. Charles II was initially reluctant to accept these conditions, but after Cromwell's campaign in Ireland crushed his Royalist supporters there, he felt compelled to accept the Scottish terms and signed the Treaty of Breda on 1 May 1650. The Scottish Parliament set about rapidly recruiting an army to support the new king and Charles set sail to Scotland, landing on 23 June. Scotland was actively rearming and the leaders of the English Commonwealth felt threatened. They pressured Thomas Fairfax, lord general of the New Model Army, to launch a preemptive attack. Fairfax accepted the commission to lead the army north to defend against the possibility of a Scottish invasion but was unwilling to strike the first blow against his former allies, believing that England and Scotland were still bound by the Solemn League and Covenant. When a formal order to attack came on 20 June, Fairfax resigned his commission. A parliamentary committee which included Cromwell, his close friend, attempted to dissuade him, pleading with him to change his mind, but Fairfax remained resolute and retired from public life. Cromwell succeeded to his office as lord general, becoming commander-in-chief of the New Model Army; he received his commission on 28 June and set out for Scotland the same day, crossing the Tweed on 22 July. Prelude Once the Treaty of Breda had been signed, the Scottish Parliament started levying men to form a new army, under the command of David Leslie. Their aim was to increase their forces to 36,000 men, but that number was never achieved; by the time Cromwell entered Scotland, Leslie had some 8,000–9,500 infantry and 2,000–3,000 cavalry, although these numbers fluctuated during the course of