The Wellesley family is an Anglo-Irish noble family of Anglo-Saxon heritage. The family was originally from Somerset, deriving its name from the City of Wells in that county, with which they had a close association. The family holds the office of Hereditary Royal Standard Bearer of Ireland, which they initially received through Grand Serjantcy. A Wellesley accompanied King Henry II of England to Ireland in 1172 as his standard bearer during the Hiberno-Norman Invasion and for this service received large grants of land in County Meath and Kildare.
It has been suggested that Guy, the first known Wellesley was made a Thegn by King Athelstan in 938 and he is said to have resided near Wells in Somerset. Furthermore, the manor of Wellesley, located in Somerset, was expressly mentioned in a charter of Edward the Confessor to the Church of Wells in 1065. In the reign of Henry I, Avenant de Wellesley was King's serjeant of all the country lying east of the river Parret in Somersetshire.
According to Burke's Peerage, the Wellesley lineage can be directly traced to Waleran de Wellesley who became first itinerant justice of Ireland in 1255. It is generally accepted that he was the first member of the family to permanently settle in Ireland. A close descendant, Sir William de Wellesley was given custody of Kildare castle by Edward II and was summoned to Parliament in 1339, receiving the title of Baron Noragh. However, the Wellesley family became extinct in the male line with the death of Garret Wesley in 1728 so a royal licence was obtained, allowing the estates and arms to be inherited by a cousin Richard Colley. Richard descended from the Wellesley's family through female line, as is shown bellow.