 Internecine conflict between the different factions weakened the colonies and made it easier for the Irish to unite against them.During this period most of the Norse colonies at Dublin, Wexford, Waterford, Cork and Limerick fell under the sway of native rulers, as the former allies of the Norsemen turned against them.It has even been claimed that Cerball mac Dúnlainge assumed the kingship of Dublin around this time (possibly with the consent of its Norse inhabitants), but there is nothing in the Irish sources to support this.