Ulpian (Dometius Ulpianus)ŭlˈpēən, d. 228, Roman jurist. He was a member of the council of the jurist Papinian. As Praetorian prefect from 222, he enjoyed the favor of the emperor Alexander Severus, and he was murdered by the jealous Praetorian Guard. Ulpian's Libri ad edictum [edicts], a statement of the policy he would follow while in office, survives only in excerpts. Much of the Corpus Juris Civilis is extracted from Ulpian's writings.