The first known written use of the term “turncoat”, denoting one who abandons his side and switches allegiance, dates to 1570. The term’s origins is said to trace back to the practice of soldiers turning their uniform coats inside out to either renounce their allegiance, or mask it as a ruse of war. Some sources trace the term as far back as the First Barons’ War (1215 – 1217), when two aristocrats changed sides from William Marshal, 1st Earl of Pembroke, to King John of England, thus literally turning their coats of arms from one party to another. Below are twenty fascinating facts about some of history’s most important turncoat commanders.
20. The Jewish Revolt Leader Who Joined the Romans

Yosef ben Matityahu (37 – 100 AD), who Latinized his name to Titus Flavius Josephus, was a leader and general who commanded Jewish forces in Galilee at the start of the First Jewish-Roman War (66 – 73 AD). Josephus turned coat after he was captured, and joined the Romans. The uprising, also known as the Great Jewish Revolt, had erupted in 66 AD after the Roman authorities responded to tax protests by arresting prominent Jews and looting the Jewish Temple in Jerusalem. That heavy handedness transformed the protests into a full blown rebellion, which forced the Romans to flee Judea. Armed bands seized forts across the country, while in Jerusalem, which the rebels captured, a national military government was organized.