Robert was born at the family seat at New Park, Moville. He was educated at Foyle College, Londonderry; Wraxall Hall School, Wiltshire; and, from 1823-5, at Addiscombe Military Seminary, Croydon, Surrey. In 1827 he was appointed to the Indian Civil Service. He married in India and brought up a family. His second son was Henry, father of Field Marshal Montgomery. Henry inherited the family estate in Ireland after his father's death.