David (son of Heraclius)
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.
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.
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.
[3][4][5] Byzantine art historian Cecily Hennessy points out that the birth of David occurred after several children of Heraclius and Martina had been born malformed or died in infancy.
[6] Heraclius had produced two children by Fabia Eudokia (Eudoxia Epiphania and Emperor Constantine III) and at least nine with Martina, most of whom were sickly, and four of whom died in infancy.
A description of the ceremony is preserved in De Ceremoniis which says that the kamelaukion (caesar cap) of Heraclonas was removed from his head and replaced with the imperial crown.
[12][14]Kaegi notes that this solemn celebration papered over tensions between branches of the imperial family and also served as an occasion for "pageantry at Constantinople in an otherwise doleful era".
[15] The Byzantine scholar Andreas Stratos emphasizes that the measures were intended to ensure a regular line of succession for the family of Heraclius.
However, the two princes were too young at the time to have taken an active role in any banishment, and the account by John of Nikiû is so contradictory that no safe conclusions can be drawn from it.
[27][30][32] As part of a compromise, David was raised to co-emperor with the regnal name Tiberius, ruling with his brother Heraclonas and their nephew Constans II.
[37] One dubious source is the Synodicon Vetus, where Tiberius is attested as the recipient of a papal letter:[38] In addition, the thrice-blessed Pope John of Rome – for he had succeeded the monothelete Honorius – assembled a divine and sacred synod and, anathematizing Sergius, Cyrus, and Pyrrhus, proclaimed two natures and energies in our Master and God Jesus Christ, and afterward he sent a decree of orthodoxy to David and Heraclius, the sons of Heraclius.
Since there were multiple emperors in 641, the mints may have resorted to reusing a depiction of three co-emperors originally intended to signify Heraclius, Constantine III and Heraclonas.
Alternatively, and with the same result, epsilon (the fifth letter of the Greek alphabet) could signify the fifth year of a lustrum cycle, which here would apply to the 15th indiction beginning on 1 September 641.
[41] Some fragmentary Egyptian papyrus documents from 641 contain dating clauses that scholars have taken to refer to David, giving the number of years since he was raised to caesar.
John relates that Martina and her sons had formed an alliance with the Bulgar ruler Kubrat and a military leader named David with the intention to deny the throne to the descendants of Constantine III.
John of Nikiû reports that Theodore "had Martina and her three sons, Heraclius, David, and Martinus, escorted forth with insolence, and he stripped them of the imperial crown, and he had their noses cut off, and he sent them in exile to Rhodes.
"[33][52][53] George Ostrogorsky and John Haldon date the deposition of Martina's sons to the end of September 641;[55][56] Warren Treadgold to c. 5 November 641,[57] while Stratos argued for January 642, accepting Theophanes' account that Heraclius died in March.
