The earliest recorded reference to the area appears in a 1427 inquisition, where it was listed as Nunton and identified as a possession of the prioress and convent of the Blessed Mary of Down, based in Downpatrick. This ecclesiastical connection is reflected in the townland's Irish name. In the early 15th century, a
carucate of land in Ballynagallagh was granted to
Sir Janico D'Artois, a Gascon noble who served as
Seneschal of Ulster. This grant was confirmed in a post-mortem inquisition following his death in 1426. Following the rebellion and subsequent conviction for treason of
Thomas FitzGerald, 10th Earl of Kildare (commonly known as Silken Thomas), during the reign of Henry VIII, the Kildare estates in Lecale, including Ballynagallagh, were confiscated by the Crown. These lands were then leased to various individuals. In 1552, the estates were restored to
Gerald FitzGerald, 11th Earl of Kildare, whose rights were confirmed by letters patent issued by Queen Mary in 1554, and reaffirmed under the joint reign of
Philip and Mary in 1555, and again by Queen Elizabeth I in 1583. == Archeology ==