4th Troop of Horse Guards

The 4th Troop of Horse Guards was the Scottish unit within the Horse Guards Regiment. It was part of the United Kingdom military establishment from 1709 to 1746, but before the Union of the Parliaments, it had been an independent unit in Scotland, sometimes referred to in modern works as the Scots Troop of Horse. The unit's establishment is usually dated to 1661, although its antecedents extend back to the fifteenth century.

The recorded history of the royal guard in Scotland dates from the 1440s, when Sir Patrick Gray is recorded as captain of the guard under King James II. A regular succession of captains is recorded from then on, but the size and organization of the unit changed several times: in 1584 it was a small mounted escort of forty veteran troopers, its lowest recorded strength, but in 1594 it reached what was probably its largest size, mustering four cavalry troops plus 400 infantry. Although the guard was retained in Scotland after the Union of the Crowns, the unit was downsized to just ten men in 1609, and it seems to have been disbanded in 1628.

After 1628, there seems to have been no separate Guard in Scotland, although when Charles I raised a Life Guard to fight in the English Civil War, it incorporated a sizable Scottish contingent, including the commanding officer, Lord Bernard Stewart.

In 1650, when Charles II landed in Scotland, a mounted regiment of Life Guards was formed, with the Earl of Eglinton as Colonel or Captain-General, and Viscount Newburgh as lieutenant-colonel and as captain of the bodyguard troop. Eglinton was captured early in 1651, but the Life Guard appears to have fought at the Battle of Worcester, after which Newburgh escaped into exile.

After the Restoration, Newburgh mustered a revived bodyguard troop in Edinburgh in March 1661, numbering four officers, five NCOs, and 120 troopers, plus a surgeon and clerk, three trumpeters and a drummer. This was a prestige unit, in which the lowest-ranking NCOs held captains' commissions from the Civil War, and the lowliest troopers were gentlemen's sons. It ranked as the senior unit of Scotland's new standing army.

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