The Isle of Man occupied a place both central and peripheral in the history of the North Atlantic. Because of its location it was, no doubt, central to the sea trade routes in and around the Irish Sea region already in the prehistorical period, and in the medieval period it played an important role in the politics of Ireland, England, Wales, and Scotland, and was by 1000 CE an important seat of Scandinavian power. Later, in a related development, Somerled Macgilbred, the first Lord of the Isles, seized the Hebrides from the King of Man, and took the title King of the Hebrides and King of Man, although the Lordship of the Isles never actually included the Isle of Man. Before and after its domination by the Norse, Man clearly was a place known to and settled by speakers of Celtic languages, from both sides of the Irish Sea. For example, in an anecdote told in the late Old Irish text known as “Cormac's Glossary” (Sanas Cormaic, dated to the late first millennium CE), the island appears as a place of exile for a lost-and-found poetess, as well as a base of mercantile operations, inhabited by Manannán mac Lir, believed by the pagan Irish to have been a god, but who was in fact, according to the author, a successful merchant and seaman. An Irish Sea Shangri-La or Bali Hai of sorts, Man seems to have held a significant place in the mythology of the Irish and to have been associated with the supernatural via its connection with the ubiquitous Manannán, who in later folklore is said to protect the island by shrouding it in mist.

Its mysterious protector notwithstanding, Man, as the historian Sir David Wilson has pointed out, did fall prey to the vicissitudes of history, undergoing various economic undulations. While there was a significant amount of commerce involving the island during the Lordship of the Isles—tellingly, a mint was established there already c. 1025—and it served as a waypoint for Scandinavian trade from Dublin up through the Irish Sea into the North Sea, after the coming of English rule c. 1400 the Isle of Man suffered a significant economic decline, changing from a trade-based to a largely self-sustaining agrarian economy.