Schechter Letter
The "Schechter Letter" (also called the "Cambridge Document") was discovered in the Cairo Geniza by Solomon Schechter.
The Letter
The Schechter Letter is a communique from an unnamed Khazar author to an unidentified Jewish dignitary. Many believe that the Schechter Letter was addressed to Hasdai ibn Shaprut by a Constantinopolitan Khazar after his first, unsuccessful attempt to correspond with the Khazar king Joseph (see Khazar Correspondence).
The Letter was included in the Genizah Collection donated by Schechter to Cambridge University in 1898. Sadly, most of the folio is unreadable and only two surviving blocs of text exist.
The conversion text
The Schechter Letter contains an account of the Khazar conversion that differs from that of the Khazar Correspondence and the Kuzari. In the Schechter Letter account, Jews from Persia and Armenia migrated to Khazaria to flee persecution, where they mingled with the nomadic Khazars, eventually assimilating almost totally. Then a strong war-leader arose (in the Schechter Letter, he is named Sabriel), who succeeded in having himself named ruler of the Khazars. Sabriel happened to be remotely descended from the early Jewish settlers, and his wife Serakh convinced him to adopt Judaism, in which his people followed him.