Thomas Moore was an Irishman who lived from 1779-1852. He had a long and varied career, as they say, which could have ended much sooner if the duel he was supposed to fight in 1806 had not been stopped by the authorities; he forever afterward had to deal with rumors that his opponent (the editor of a critical review) had been given an unloaded pistol.
Eventually Moore was persuaded to write lyrics to some already-established Irish airs. These songs included the more-famous “The Last Rose of Summer” and “Believe Me, If All These Endearing Young Charms.”