Newell is Ó Tnúthghail in Irish. This was a minor sept located on the border of the counties of Kildare and Meath and the name was first anglicized as O'Knowell, from where the modern Knowles come. As Newill it appeared in the Hearth Money Rolls for Co. Tyrone (1664). Three Knowles were distinguished in various branches of literature in the nineteenth century. Three Newells, too, all from the Belfast area, are noteworthy: one Edward J. Newell (1771-1798) as an informer, Alexander Newell (1824-1893) was a distinguished scientist and Hugh Newell (b.1830) an artist of repute in America. Source: More Irish Families, Edward MacLysaght, Dublin: Irish Academic Press, 1996.
Surname explanation: "The name carries us to the gently rising slopes in the woods, grassy and free of timber, the old form of Knowles being de la Cnolle which means of the hill." Also termed as at the knoll or summit.