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 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 for Scotland, landing on 23 June. Opposing forces Infantry Infantry formations, equipment and tactics were similar in both armies. The regiment was the standard tactical unit, but their size was not standardised and varied greatly. An infantry regiment was composed of both musketeers and pikemen. The musketeers were armed with muskets possessing barrels and, mostly, matchlock firing mechanisms. These relied on the glowing end of a length of slow match, thin cord soaked in saltpetre, igniting the weapon's priming powder when the trigger was pulled. These were reliable and robust weapons. In 1650 musketeer tactics were in the middle of a transition from firing one rank at a time so as to maintain a steady fire, to the entire unit discharging a volley simultaneously for shock effect. Pikemen were equipped with pikes: long wooden shafts tipped with steel points. Pikes as issued in both armies were , but on the march they were commonly cut down to a more wieldy or so. The pikemen carried basic swords and typically wore a steel helmet but no other armour. Military manuals of the time suggested a ratio of two musketeers for each pikeman, but in practice commanders usually attempted to maximise the number of musketeers and a higher ratio was the rule. Both armies organised their infantry regiments into brigades of three regiments each, which were typically deployed with two regiments abreast and the third behind as a reserve. The men in each unit would form up four or five ranks deep and in a relatively loose formation, with about of frontage per file; so an infantry regiment of 600 might form up 120 men wide and 5 deep, giving it a frontage of and a depth of . The pikemen would be placed in the centre of