David (son of Heraclius)

David (Greek: Δαυίδ; fl. 630–641) was one of three co-emperors of Byzantium for a few months in late 641, and had the regnal name Tiberius. David was the son of Emperor Heraclius and his wife and niece Empress Martina. He was born after the emperor and empress had visited Jerusalem and his given name reflects a deliberate attempt to link the imperial family with the Biblical David. The David Plates, which depict the life of King David, may likewise have been created for the young prince or to commemorate his birth. David was given the senior court title caesar in 638, in a ceremony during which he received the kamelaukion cap previously worn by his older brother Heraclonas.

After the death of Emperor Heraclius in February 641, when David was 10 years old, a power struggle ensued between different branches of the imperial family. As part of a compromise, David was raised to be co-emperor, ruling with his brother Heraclonas and their nephew Constans II. The Byzantine state faced serious challenges while Tiberius was co-emperor, with the ongoing Muslim conquest of Egypt and continuing religious strife over monothelitism and other Christological doctrines. All three emperors were children and the Empress Dowager Martina acted as regent. Martina was deeply unpopular due to her incestuous relationship with Heraclius, her unconventional habits, and her ambition. Her regime was deposed in a rebellion, probably by January 642. She and her sons were exiled to Rhodes and, in an early example of Byzantine political mutilation, Martina's tongue was cut out and the noses of her sons were cut off. There is no further historical record of Tiberius, and some historians speculate that he and his family lived out the rest of their lives peacefully.

Four of the David Plates depict (clockwise) David's being summoned by the prophet Samuel, being anointed by him, receiving Saul's armor, and battling Goliath. From the collection of the Metropolitan Museum of Art, New York.