428

Millennium:	1st millennium
Centuries:	4th century – 5th century – 6th century
Decades:	390s 400s 410s – 420s – 430s 440s 450s
Years:	425 426 427 – 428 – 429 430 431

Year 428 (CDXXVIII) was a leap year starting on Sunday of the Julian calendar.

Events

Bonifacius, Roman governor of Africa, asks for help from the Vandals in his revolt.
Flavius Felix is elected consul for the Western Empire.

King Gunderic, age 49, dies after a reign of 21 years. He is succeeded by his half-brother Genseric.
King Vortigern asks Germanic warriors to help him strengthen his position in Britain. He hires Saxons as mercenaries to fight against the Picts and the Scots beyond Hadrian's Wall.
Chlodio, king of the Salian Franks, invades Northern Gaul. He defeats the Roman army at Cambrai. He extends his kingdom south to the River Somme. Tournai (modern Belgium) becomes his residence.

Artaxias IV, last king of Greater Armenia, is deposed by Bahram V. The Arshakuni Dynasty ends and the kingdom becomes a province of the Persian Empire.

April 10 – Nestorius is made patriarch of Constantinople. He preaches a new doctrine that will be called Nestorianism. It comes under immediate attack from pope Celestine I and Cyril of Alexandria.
Hydatius becomes bishop of Aquae Flaviae in Gallaecia (modern Chaves) in Portugal.
John succeeds Theodotus as patriarch of Antioch, and gives his support to Nestorius.
Euthymius the Great builds a monastery in Palestine, near the Dead Sea.

Traina, Giusto (2011). 428 AD: An Ordinary Year at the End of the Roman Empire. Princeton University Press. ISBN 978-0-691-15025-3.