Genealogy
Archives in Spain and Ireland show that Ambrose O'Higgins was the son of Charles O'Higgins, of Ballynary, County Sligo (son of Roger O'Higgins, of Ballynary, County Sligo, and wife Margaret Brehan), and wife and cousin Margaret O'Higgins (daughter of William O'Higgins and wife Winnifred O'Fallon). Charles O'Higgins' grandfather, Sean Duff O'Higgins, held the Gaelic territorial title of Tiarna or Lord of Ballinary, and he was married to an O'Conor, daughter of the Royal House of O'Conor of Ballintober Castle, which ruled Ireland until the year 1000.
The O'Higgins family were a sept of the O'Neill dynasty who migrated to Sligo in the 12th century. As Gaelic nobles they had owned great expanses of land particularly in the Irish counties of Sligo and Westmeath, but with the expropriations of Catholics by Oliver Cromwell, and the deportation of tenants to County Sligo after the Cromwellian conquest of Ireland ca. 1654, the O'Higgins' lands became smaller and smaller. Due to this encroachment into their land, the O'Higgins family migrated to Summerhill in County Meath, where they became lowly tenant farmers and worked in the service of the Rowley-Langford family. Their descendents remain in Summerhill however, Bridget O'Higgins who died in 1947 was the last in Summerhill to carry the family name as others had emigrated to the USA and migrated to Dublin. The O'Higgins graves are located in The Moy and Agher cemeteries, both within the boundaries of the Roman Catholic parish of Dangan in Summerhill.
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