Theophylact (son of Michael I)

Theophylact
Emperor of the Romans
A young prince, most likely Theophylact, being crowned junior emperor by his father, miniature from the 12th century Madrid Skylitzes.
Byzantine emperor
Co-reign	25 December 811 – 11 July 813
Predecessor	Michael I Rangabe
Successor	Leo V the Armenian
Senior emperor	Michael I Rangabe
Born	c. 793
Died	15 January 849 Plate Island
Dynasty	Nikephorian dynasty
Father	Michael I Rangabe
Mother	Prokopia

Theophylact or Theophylaktos (Greek: Θεοφύλακτος; c. 793 – 15 January 849) was the eldest son of the Byzantine emperor Michael I Rangabe (r. 811–813) and grandson, on his mother's side, of Nikephoros I (r. 802–811). He was junior co-emperor alongside his father for the duration of the latter's reign, and was tonsured, castrated, and exiled to Plate Island after his overthrow, under the monastic name Eustratius.