The Gallgoidel, also known as the Norse-Gaels, were a people of mixed Gaelic and Norse ancestry who dominated the Irish Sea and the Hebrides from the 9th to 12th centuries. The Gallgoidel were descended from Vikings who adopted Gaelic culture and intermarried with Gaelic women, settling in Ireland and Scotland; they became the ancestors of the Scottish clans MacDonald, MacDougall, and MacLeod and the Irish clans MacIvor, MacAskill, and MacCotter, and they were eventually assimilated into the Irish and Scottish peoples and disappeared as a distinct group. In Scotland, many of the Norse-Gaels became gallowglass mercenaries.