Heraclius (; 626 – 642), known by the diminutive Heraclonas or Heracleonas (), and sometimes called Heraclius II, was the son of Heraclius and his niece Martina. His father had stipulated in his will that both of his sons, Heraclonas and Constantine III, should rule jointly upon his death. Heraclius also specified that his wife, Martina, was to be called "Mother and Empress" insofar as she might have influence at court as well. The emperor Heraclius died in February 641 from edema. When Martina made the late Emperor's will public she faced staunch resistance to her playing any active role in government, but both Heraclonas and Constantine were proclaimed joint-emperors in February 641 without incident. After Constantine died of tuberculosis in May 641, Heraclonas became sole emperor, under the regency of his mother due to his young age. He reigned until October or November 641, when he was overthrown by Valentinus, a general and usurper of Armenian extract, who installed Constans II, the son of Constantine III. Valentinus had Heraclonas' nose cut off, then exiled him to Rhodes, where he is believed to have died in the following year. Early life and family Heraclonas was born in 626, in the suburban Palace of Sophianae. He was the son of Emperor Heraclius, and his niece-wife Martina, and was born while Heraclius campaigned in the east against the Persians. Under Heraclius, the Byzantine Empire was invaded in 639 by the Arabs, due to the failure of the Theme of Mesopotamia to pay tribute. The cities of Edessa and Dara were quickly captured. In the same year, another group of Arabs, led by 'Amr ibn al-'As, invaded Byzantine Egypt. He quickly occupied the coastal towns of Egypt, but was unable to cross the Nile, due to stiff resistance by Byzantine forces led by John. After a bloody battle between John and 'Amr, in which John perished, 'Amr was forced to appeal to the Rashidun Caliph Umar for more troops. John was replaced by another general, Theodore, who gathered his forces around Babylon Fortress, a major fortress in Egypt. By summer 640, 'Amr's forces had swelled to around 15,000 men. With these men, 'Amr decisively defeated Theodore north of Babylon, before laying siege to the fortress itself. Life Heraclonas was made by Heraclius on 1 January 632, and further elevated to (co-emperor) on 4 July 638, at a ceremony in the chapel of Saint