Raising and disbanding regiments was, of course, the cheaper option. By the 1660's the Standing Army was sufficiently large for disputes to break out between the colonels of regiments as to which regiments were more senior than the others and therefore entitled to stand in a particular order in the line of battle, march ahead of others in the line of march and be listed by order of seniority. In the military context establishment means organisation and the organised body of men maintained at the expense of any sovereign or state for a military purpose.
Establishment can also mean the quota of officers and men that make up a regiment of ship.
These separate Establishments were a reflection of the history of the three separate Kingdoms with their once independent government, defence and tax raising status. The separate Standing Armies of Scotland and Ireland ceased to exist in 1689 as purely Scottish and Irish defence forces and the armies of England, Scotland and Ireland became one British Army. This British Army had three establishments, the English, the Scottish and the Irish and the Regiments and men which made up those establishments were stationed indiscriminately in each of the three Kingdoms regardless of nationality. The Scottish Establishment ceased to exist after the Act of Union of 1707 and the Irish Establishment after the Act of Union of 1800. The Establishment is thereafter referred to as the British Establishment.