“Constitutio 55” issued by Leo III [Byzantine Empire; Present-day Turkey] [Unconfirmed]
Commentary from other sources:
1) “Leo III required that Jews live according to the Christian rites (“ut Judaei secundum christianismi ritum vivant”) and threatened those who deviated from the Christian customs and attempted to return to their Jewish customs and teachings with apostasy.”
Scherer, Johann E.: Die Rechtverhältnisse der Juden in den deutsch-österreichischen Ländern (Leipzig; 1901) p. 16