 The MacDonnells of Antrim were a sept of the powerful Clan Donald of the royal Clann Somhairle, (see Lords of the Isles), that the English crown had attempted to cultivate since the early 14th century in its efforts to influence the course of politics in Scotland.The MacDonnells established a growing presence in Ireland throughout the 15th and 16th centuries, and played a crucial role in the politics of 17th century Ireland.Today the surname is predominantly spelled McDonnell in Ireland and abroad.