Ryan, ó Maoilriain, ó Riain A Gaelic surname meaning descendants of Maolrian. The personal name Rian is most likely a diminutive of Rí meaning a ‘king’. A sept of Leinster origin who settled in the thirteenth or fourteenth century in Uaithne Tíre and Uaithne Cliach, now the baronies of Owney in Tipperary and Owneybeg in east Limerick. Should be distinguished from ó Riain meaning descendent of Riaghan or Rian. A sept in Carlow who were lords of Uí Dhróna, now the barony of Idrone. ó Ruadháin, meaning descendent of Ruadhán; a diminutive Ruadh meaning ‘red haired’. Also anglicised as O’Ruane. A sept of the Uí Fiachrach in Mayo and also A sept of the Uí Mhaine in Galway. In 1890 Ryan was the eight most numerous surname in Ireland, the estimated number of bearers was 32,000, and it was the most numerous surname in Limerick and Tipperary. In that year the surname was also to be found in Dublin, Cork, Waterford, Kilkenny, Wexford, Clare and Galway. In the United States Ryan is the 203rd most numerous surname with an estimated 140,250 bearers. It is numerous in the states of Connecticut, New Jersey, and New York. In England and Wales in 1996 it was the 135th most numerous surname.