The origin of the MacNeills of Taynish, Gigha and Colonsay is obscure. They were hereditary keepers of Castle Sween under the Lords of the Isles during the 15th and 16th centuries. The MacNeill of Gigha, was known as the "chief and principal of the clan and surname of Macneils" in 1530. However, as the power of the Campbells grew and spread into the Inner Hebrides, the influence of the MacNeills of Gigha decreased. At about this time the MacNeils on the more remote island of Barra, far removed from Campbell power, began to grow in prominence and for a long time since have been regarded as "Chief of the Clan and Name".