Late 3rd century: Birth of Theognis
Before 325: Theognis is ordained bishop of Nicaea
325: Theognis’ participation in the First Ecumenical Council at Nicaea. He refuses to sign the anathemas against Arius
325-328: Exile of Theognis and of other Arians
328: Restoration of Theognis of Nicaea and of Eusebios of Nikomedeia in their bishopric sees
330-335: Theognis’ active participation in the Arian councils at Antioch, Caesarea of Palestine, Tyros and Jerusalem
February 336: Theognis’ active participation in the council of Constantinople that deposed Athanasios of Alexandria and Markellos of Ancyra
341: Council at Antioch. Composition of Arians’ confession of faith. Replacement of the term “homoousios” (consubstantial) with the term “homoiousios” (of similar substance). Ulfilas ordained bishop of the Goths
342: Election of the Arian Makedonios as bishop of Constantinople; turmoil and disputes. Last mentions of Theognis in the sources
After 342: Death of Theognis