In the 1800s, a movement spread across Great Britain that convinced thousands of Englishmen they were part of an ancient Jewish tribe. It was based on a legend about an evangelizer, Joseph of Arimathea. Another ancient legend — this time about Prince Menelik and the stolen Ark of the Covenant — places the lost tribes in Ethiopia. More recently, claims by the Lemba people of South Africa spurred one researcher, known as the British Indiana Jones, even deeper into the mystery.