On May 22, 334 BC, the Macedonian army of Alexander the Great defeated Darius III of Persia in the Battle of the Granicus. From the introduction:
"The Battle of the Granicus in May 334 BCE was Alexander the Great's (356-323 BCE) first major victory against the forces of the Achaemenid Empire. Alexander had crossed the Hellespont with his combined Macedonian and Greek forces and stepped upon the shores of Anatolia. His goal was simple: to defeat Darius III (r. 336-330 BCE) and conquer the vast Persian Empire. In May 334 BCE he had his first opportunity when he faced the Persians on the banks of the River Granicus. After this victory against his satraps, he would meet Darius in battle twice, at the Battle of Issus and then at the Battle of Gaugamela."