John Dawney was born to Nicholas Dawney [Dawnay] and his wife, Elizabeth at Madfordferry, Somerset. He became a famous soldier and embarked with King Edward III of England on his expedition to Honfleur in 1346. He fought in the victory at the Battle of Crécy, for which he was knighted. He died shortly afterwards. His will is recorded in Inquisitions Post Mortem in the year 1347/8.
He married Sybil Treverbin, of a Cornish family extraction. They had only one surviving child, Emmeline, called Emme, who married Sir Edward Courtenay of Goodrington [Godlington], third son of Hugh, 2nd Earl of Devon. Emme brought a great estate to the Courtenay dynasty.