The Island, originally covered in Hazel and Bog Oak, was settled by Celts and then Vikings before succumbing to a full-blown Viking invasion. Its commanding position in the Irish Sea and defensive terrain.
Andreas Star Fort in the North of the Island - the first obstacle to be overcome by the Parliamentarian forces.
The English Civil War - the Isle of Man both supplied troops to the Royalist side and was subsequently invaded by Parliamentarian Forces.
Warfare in the Island, other than mostly local disputes & minor raids from Ireland and no doubt the Picts & Caledonians, materialised quite soon after the Romans left Britain.
With settlement by Irish "adventurers" in the late 4th & early 5th Centuries came the North Welsh followed by the Saxons under the Duke of Northumbria. Following the withdrawal of the Northumbrians came significant Viking invasions that took over and created a brief, but significant empire. What followed was several centuries of political & military intrigue involving Viking, English & Scottish intervention before long-term peace & prosperity was finally achieved. There was of course smuggling... the Island being in a prime geographical location to assist with this endeavour.
We will be providing detailed scenarios on a range of skirmishes and small battles from this period, both real and hypothetical. There is of course the battle of SkyHill...... we'll be discussing that and creating a campaign for Godred Crovan's invasion (he had 3 attempts).
What Have the Romans Ever Done for Us? One of the biggest What ifs of perhaps Did they? was the Romans relationship to the Isle of Man. The official history is that they never came, despite the Islands prominent position in the Irish Sea and frequent raiding by the Irish of the west coast of Britain. The Isle of Man would have been a significant stepping off point for any raids and of course a safe haven, yet the Irish were not known to have landed on the Island until the Roman military had vacated Roman Britain.
From the Island you can (on a clear day) see Ireland, Scotland, England & Wales and you don't have to be that high up to do this.
By the way they did find a Roman Army votive altar in Castletown in the early part of the 19th Century, but the casual dismissal of the Bishop it was deemed to have been brought over in 1726, years after the foundations in which the altar was found were constructed.
Did the Romans land? Did they possibly occupy even if only temporarily? We don't know, but it seems logical that they did as by denying the Island to the Irish raiders they made Roman Britain far safer.
The Romans did have at least one "trading settlements" on the East Coast of Ireland so perhaps more information will come to light..... or maybe we'll just wargame it to see whether or not leaving the Island alone was a good idea or not.
The last big military action was at the end of the Civil War as the Royalist Forces on the Island succumbed to a Parliamentarian invasion and a local Manx Rebellion.