On the twenty-eighth of this month (June), we commemorate the righteous and blessed Sergios the Magistros, who established the Monastery of the Most Holy Theotokos in the Gulf of Nicomedia, which became known as Niketiatou.
In this life Sergios was a magistros,
Now he shows forth in heaven as God's magistros.
Sergios was born in the village of Niketia, near Amastris in Paphlagonia, in the early ninth century. He was a member of the Amorian dynasty, and a close relative, possibly the uncle, of Empress Theodora, the wife of Emperor Theophilos (r. 829–842) and mother of Michael III (r. 842–867).
Under Theophilos, he became one of the leading members of the Roman Senate, reaching the supreme court rank of magistros. Seals attributed to him also record him having progressively advanced through the levels of hypatos, anthypatos, protospatharios and patrikios, and having held the office of General Logothete or Logothete of the Drome (depending on the reading of the seals).
In 843, Sergios was instrumental, along with the logothete Theoktistos and Theodora's brothers, Bardas and Petronas, in bringing about the final abandonment of Iconoclasm and the restoration of the veneration of Icons.
In the same year, he was entrusted with leading an expedition against the Emirate of Crete, but all other sources record that Theoktistos led the campaign. It is possible, however, that Sergios was left behind when Theoktistos was forced to hurriedly return to Constantinople. Sergios soon after died on Crete, where the Roman forces were defeated by the Arabs, and was initially buried on the island in a Monastery that became known after him as tou Magistrou ("of the Magistros"). He was later moved to a Monastery of the Theotokos in the Gulf of Nicomedia, which he had previously founded and which in turn became known as tou Niketiatou ("of the Niketiates") thereafter.