Roger O'Shaughnessy

Roger O'Shaughnessy, The O'Shaughnessy (died 1690), was a Captain in the Irish army of James II of England. He was present at the Battle of the Boyne, dying ten days after. In 1697 Roger's estates were granted to Sir Thomas Prendergast, 1st Baronet, and the O'Shaughnessy family were never able to recover them.

He married Helen, daughter of Conor O'Brien, a son of Donogh O'Brien, 4th Earl of Thomond. Their sons were Dermot O'Shaughnessy and Major General William O'Shaughnessy, The O'Shaughnessy.