Flavius Phocas Augustus, Byzantine Emperor (reigned 602–610), ascended the throne from the Emperor Maurice, and was himself overthrown by Heraclius after losing a civil war. Almost nothing is known of Phocas's early life, although he may have been a native of Thrace. By 600, he was a subaltern officer in the Roman army that served in the Balkans, and apparently was viewed as a leader by his fellow soldiers. Wikipedia
The definitive Wikipedia entry for Phocas. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Phocas
