Papa bar Aggai[1] (died c. 327/328) was the Chaldean Bishop of Seleucia-Ctesiphon, the capital of Sassanid Persia, in the late 3rd and early 4th century.
Some historians describe him as the founding figure of the Church of the East, though according to Syriac tradition, he was simply continuing a line of leaders, such as Mar Mari, that stretched back to Thomas the Apostle.
[citation needed] During his tenure Papa made a substantial and controversial reorganization of the Persian church, setting himself up as head of a hierarchy of other bishops.
[dubious – discuss] His changes, especially his attempt to establish the bishopric at Seleucia as the authority over the rest of the Persian Church had strong opposition.
"[8] The sacrilege stunned the council's attendees, but then Papa fell senseless, struck with paralysis or apoplexy, or possibly a stroke.