Locally raised military force formed for the defence of the Isle of Man during the later eighteenth century.

The proposal emerged during the renewed threat of war in 1779. Lieutenant-Governor Dawson reported that the Island required stronger defence and suggested raising companies of fencibles alongside a request for regular troops. The Keys also discussed measures for increasing the available manpower.

By August 1779 Dawson was asking for 300 regular troops and considering three companies of fencibles. The surviving correspondence then records lists of potential officers and negotiations with the Duke of Atholl, the Keys and ministers in London.

The force proved difficult to organise. In February 1780 Dawson sent a report which included a memorial from the Keys and described serious problems with enlistment. The Duke of Atholl separately offered to fund and appoint the officers of one company, arguing from his position as the largest territorial proprietor on the Island.

The Fencibles remained part of Manx defence planning until the return of peace. In February 1783 Dawson reported on the probable disbandment of the force, while continuing to argue that the Island still required troops.

The name survived into later military administration. Home Office papers from 1807 include correspondence over the cost of providing sentry boxes for the Manx Fencibles, showing that locally raised defensive forces continued to form part of the Island’s military establishment.