Small standing military establishment maintained by the Lords of Man before Revestment.

After the restoration of the Stanley government the much larger Civil War forces were reduced. A surviving reconstruction from the disbursement accounts describes an establishment of about twenty men at Castle Rushen and Derby Fort, with a smaller garrison at Peel, a few men at Douglas Fort and a token presence at Ramsey.

The garrison remained fairly stable between 1670 and 1765. The accounts record the officers and soldiers receiving salary or pension, together with specialist trades. At Castle Rushen the establishment could include a gunsmith and apprentice, while some soldiers also worked as smiths, saddlers or glaziers.

The soldiers were not confined to military defence. Constables had responsibility for maintaining order in the towns, and soldiers supported both the civil and ecclesiastical courts. Orders survive requiring garrison soldiers to compel boat crews to carry documents or persons on official business and to commit those who refused.

The forts also functioned as places of confinement. Contemporary and later accounts of Castle Rushen repeatedly refer to prisoners and to the soldiers responsible for guarding them.

The old garrison establishment ended with Revestment in 1765, when the Crown acquired the Island and military administration began to pass into British departmental structures.