Year 622
Byzantine–Sasanian War: Emperor Heraclius sails from Constantinople with an expeditionary force (probably 50,000 men) and starts a counter-offensive against the Persian Empire. His young son, Constantine III, is left behind as regent under the charge of Sergius I, patriarch of Constantinople, and patrician Bonus. He lands a few days later at the junction of Cilicia and Syria, near Alexandretta and ancient Issus.
The heck did I just copy from a Wiki Article...