Robert Jephson was born in Ireland in 1736, the son of Archdeacon John Jephson.
His education was at Ryder's grammar school and then the Reverend Roger Ford's school before he was admitted to Trinity College, Dublin in 1751. He left without a degree.
Jephson now joined the British Army with a commission in the 73rd Regiment of Foot. Among his postings was one to the Caribbean. He left, for health reasons and retired with the rank of Captain.
An appointment was offered as master of the horse to the lord-lieutenant of Ireland. Whilst in this office he wrote and had published, in the Mercury newspaper, a collection of articles that defended the lord-lieutenant’s administration. These were later published in book form as ‘The Bachelor’, or ‘Speculations of Jeoffry Wagstaffe’.
Jepson held the office under twelve successive viceroys and gained a pension of £300, which was later doubled.
He entered the Irish House of Commons in 1773 and sat for St Johnstown (County Longford) until 1776. Between 1777 and 1783, he served as Member of Parliament for Old Leighlin and thereafter represented Granard from 1783 to 1790
In 1775 he added playwright, dramatist and poet to his military and political career strands. His plays gathered much interest. Among them his tragedy ‘Braganza’ was successfully performed at Drury Lane in 1775, ‘Conspiracy’ in 1796, ‘The Law of Lombardy’ in 1779, and ‘The Count of Narbonne’ (adapted from Horace Walpole’s ‘The Castle of Otranto’) at Covent Garden in 1781.
In 1788 he published ‘Extempore Ludicrous Miltonic Verses’ and, in 1794, the heroic poem ‘Roman Portraits’, and ‘The Confessions of Jacques Baptiste Couteau’, a satire on the excesses of the French Revolution.
Robert Jephson died at Blackrock, near Dublin, on the 31st of May 1803.