Chalcedon
The site of Chalcedon is located on a small peninsula on the north coast of the Sea of Marmara, near the mouth of the Bosphorus. A stream, called the Chalcis or Chalcedon in antiquity and now known as the Kurbağalıdere (Turkish: "stream with frogs"), flows into Fenerbahçe bay. There Greek colonists from Megara in Attica founded the settlement of Chalcedon in 685 BC, some seventeen years before Byzantium.
Council of Chalcedon
The Council of Chalcedon was convened by Emperor Marcian, with the reluctant approval of Pope Leo the Great, to set aside the 449 Second Council of Ephesus which was named the "Latrocinium" or "Robber Council" by Pope Leo. The Council of Chalcedon issued the Chalcedonian Definition, which repudiated the notion of a single nature in Christ, and declared that he has two natures in one person and hypostasis. It also insisted on the completeness of his two natures: Godhead and manhood. The council also issued 27 disciplinary canons governing church administration and authority. In a further decree, later known as canon 28, the bishops declared that the See of Constantinople (New Rome) had the patriarchal status with "equal privileges" ("τῶν ἴσων ἀπολαύουσαν" in Greek, "aequalibus privilegiis" in Latin) to the See of Rome. No reference was made in Canon 28 to the bishops of Rome or Constantinople having their authority from being successors to Peter or Andrew respectively. Instead, the stated reasons in the actual text of the Canon that the episcopacy of these cities had been granted their status was the importance of these cities as major cities of the empire of the time.