Marcian (Latin: Flavius Marcianus Augustus; 392 – 27 January 457) was Eastern Roman Emperor from 450 to 457. Marcian's rule marked a recovery of the Eastern Empire, which the Emperor protected from external menaces and reformed economically and financially. On the other side, the isolationistic policies of Marcian left the Western Roman Empire without help against barbarian attacks, which materialized in the Italian campaigns of Attila and in the Vandal sack of Rome (455). The Eastern Orthodox Church recognizes Marcian as a saint for his role in convoking the Council of Chalcedon.

Marcian was born in 392 in Illyricum or Thracia. The son of a soldier, he spent his early life as an obscure soldier, member of a military unit located at Philippopolis. Marcian was dispatched with his unit for a war against the Sassanids (probably the Roman-Sassanid war of 421–422), but along the road East he fell ill in Lycia; at this time he might have already been tribunus and commander of his unit.

After recovering from his illness, he went to Constantinople, where he served for fifteen years as domesticus under the generals Ardaburius and Aspar. In 431/434, while fighting in Africa under Aspar, Marcian was taken prisoner by the Vandals; according to a later legend, he was brought before King Geiseric (428–477), who knew by an omen that Marcian was to be Emperor and was released on his oath never to take up arms against the Vandals.

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