Bulgarus

Bulgarus was a twelfth-century Italian jurist, born in Bologna. He has been confused with Bulgarinus, another 15th-century jurist.
He was the most celebrated of the famous Four Doctors of the law school of the University of Bologna, probably because his school promoted Roman emperors, such as Justinian I, as the highest authority. Bulgarus was regarded as the Chrysostom of the Glossators, being frequently designated by the title of the "Golden Mouth" (os aureum). He died in 1166 at a very advanced age.