The English Civil War was a period of unparalleled brutality across the British Isles. The conflict pitted fathers against sons, tore families apart and divided many communities for generations. Against this violent backdrop, the story of Lady Bankes and the defence and ultimate capture of Corfe Castle is one of the more romantic and audacious tales.
Corfe Castle was one of England’s first Norman castles and occupied an enviably strong position commanding a gap in the Purbeck Hills between Wareham and Swanage in Dorset. It was originally a royal fortress, and remained controlled by the Crown until Elizabeth I sold it to Sir Christopher Hatton in 1572. In the seventeenth century it passed into the hands of Sir John Bankes and his indominatable wife, Lady Mary Bankes.
Sir John was the Attorney General to Charles I and a committed Royalist. He stayed by the King’s side in Oxford whilst his wife remained at Corfe Castle. Unfortunately, most of the rest of southern England, including Dorset, was under firm Parliamentary control. Corfe Castle was put to siege, with a handful of Royalists commanded by Lady Bankes foiling a Parliamentary force of several hundred.
At this point, the Parliamentary forces under Colonel Bingham had the simple if brilliant idea of turning their coats inside out. The lining of their uniforms was in Royalist colours and the castle’s defender’s were tricked into believing they had been relieved. Parliamentary troops thus breached walls, gained entry to the keep and captured the castle.
Unfortunately, this story is not borne out by the word’s printed history. The Oxford English Dictionary’s earliest entry for turncoat is 1570, predating the English Civil War by over 70 years.
This leads to another, probably apophyrical story of the word’s origins. The 1898 edition of Brewer’s Dictionary of Phrase and Fable has an admirably constrained explanation of the word’s supposed origin in the actions of the Duke of Saxony:
“As the dominions of the duke of Saxony were bounded in part by France, one of the early dukes hit upon the device of a coat blue one side, and white the other. When he wished to be thought in the French interest he wore the white outside; otherwise the outside colour was blue.”
A definitive etymology is impossible, but it is more likely that the word was employed to describe anyone who hid their allegiances by turning their coat inside out and thus hiding their party colours or heraldic badges. You should never let the truth get in the way of a good story, but it is always a good to understand the more likely (if, admittedly, more boring) facts behind the story!