While the Church was confused by the heretical Nestorians, another disorder happened. The see was vacant, and the prievious contestants Philip the presbyter the Sidetes and the favourable among the people Proklus were living.

For months after the condemation of Nestorios, Proklos was put aside again, because if he were to ascend to the patriarchal see, holy canons would be broken. Hence the emperor with the Synod met together and decided to elect the presbyter Maximian, or, according to the patriarchal list of Nikiphoros, Maximus.

He was ordained on the 25th of October; and his election was announced by the Emperor and the Synod to the Pope of Rome Kælestinus and unfittingly was approved by him, which was completely unnecessary at that time or ever prior or after that time. The Patriarchal catalogues recall his overseeing lasting from 2 years and 5 months, except for the list of Kallistos, which instead of 5 months writes 5 days. According to another list, 10 months.

Patriarch Maximian was born in Rome; he was a presbyter of the Church of Constantinople, ordained by Sininios, uneducated, but ascetic his his life, and had a good fame among Christians, because with his own expenses he constructed monuments to bury the departed. Under his Patriarchy, the Church enjoyed a thorough peace.

Maximian died on the 12th April 433, on the day of Holy Thursday.

From the events under Maximian, we know about the Synod which he summoned in 431 in Constantinople, and which deposed the Bishops Helladios of Tarsus, Eutherius of Tyana, Himerius of Nicomedia, and Dorotheos of Markianoupolis, who belonged to the party of Patriarch John of Antioch, a friend being of Nestorius.

The Eastern Orthodox Church honours the memory of Maximian on the 21st of April. Prior to the 12th century, it feasted it on the 20th of November.