A family who were settled on the Galway/Mayo border at Cloghans, parish of Kilmainemore, barony of Kilmaine, county Mayo, from the mid 17th century, which according to Burke's ''Landed Gentry'' they purchased in 1663. By the mid 19th century the Lewin estate was mainly in the parishes of Kilcommon and Kilmainemore, county Mayo and Kilconla, barony of Dunmore, county Galway. In October 1851, Kilshanvoy, an estate of 1266 acres in county Galway held from the Bishop of Meath and 890 acres in the parish of Kilcommon, county Mayo were advertised for sale by the Lewin family in the Encumbered Estates' Court, however only Knockroe and Cloghansmore appear to have been sold to Martin P.Costello. The Lewins still retained much the same acreage in both counties in 1876. Some information about the early 20th century generation of this family may be found in the Tighe of Rosanna Papers.