Mithradates defeated Cotta, the Roman consul, at Chalcedon; but Lucullus worsted him, and drove him in 72 to take refuge in Armenia with his son-in-law Tigranes.
The date of his death is uncertain, but it must have been at least six or seven years later than the council of Chalcedon (451).
Besides this work Theodoret has also left us a church history in five books, from 324 to 429, which was published shortly before the council of Chalcedon.
The third and fourth oecumenical synods (Ephesus, 43 1; Chalcedon, 451) were primarily tribunals for the trials of Nestorius and Dioscorus; it was secondarily that they became organs of the universal episcopate for the definition of the faith, or legislative assemblies for the enactment of canons.
At Chalcedon, on the other hand, the imperial commissioners decided points of order, kept the synod to the question, took the votes and adjourned the court.