John (nephew of the consul Vitalian)

John (Latin: Ioannes, Greek: Ίωάννης, fl. 537–553), also known as John the Sanguinary, was a Byzantine general under Justinian I (r. 527–565) and took an active part in the Gothic War (535–554) against the Ostrogoths (Goths). He was the nephew of the rebel Vitalian, and later in life he married Justina, the daughter of Justinian's cousin Germanus. By 537, he had gained a reputation for bravery and command ability. He was tasked by Justinian with bringing supplies and reinforcements to Belisarius, who was defending Rome from a numerically superior Gothic army. Following his arrival, Belisarius assigned John to raid the Picenum region. John took the initiative and captured the strategically important city of Ariminum due to its proximity to the Gothic capital, Ravenna. The loss of Ariminum forced the Goths to abandon the siege of Rome and march north toward their capital. Despite his success, he disobeyed Belisarius's orders to leave Ariminum, and John was soon trapped by Gothic forces advancing from Rome. Belisarius was able to save him in the Siege of Ariminum (538); however, John refused to thank him. John's insubordination became a focal point in the fracturing Byzantine leadership, leading to the destruction of Milan. In the final part of the Gothic War, he followed Narses and defeated the Goths at the Battle of Taginae and Mons Lactarius, which ended the war.