The Armstrong baronetcy, of Gallen Priory in the King's County, was created on 18 September 1841 for Andrew Armstrong, Receiver-General of Stamps in Ireland and Member of Parliament for King's County from 1841 to 1852. The Armstrong family was Scotch-Irish, originally from the Scottish Borders.
The 3rd Baronet was High Sheriff of King's County in 1914.
Armstrong baronets, of Gallen Priory (1841)
Sir Andrew Armstrong, 1st Baronet (1786–1863)
Sir Edmund Frederick Armstrong, 2nd Baronet (1836–1899)
Sir Andrew Harvey Armstrong, 3rd Baronet (1866–1922)
Sir Nesbitt William Armstrong, 4th Baronet (1875–1953)
Sir Andrew St Clare Armstrong, 5th Baronet (1912–1987)
Sir Andrew Clarence Francis Armstrong, CMG, 6th Baronet (1907–1997)
Sir Christopher John Edmund Stuart Armstrong, 7th Baronet (born 1940)
The heir apparent is the present holder's son Charles Andrew Armstrong (born 1973).