The Battle of Chaeronea, fought on the 2nd of August 338 BC, was the final conclusion of the Fourth Sacred War which saw Philip II of Macedon elevated as absolute ruler among the Greek city states. The primary contestants were the Macedonians and an allied army primarily from Athens and Thebes.
Philip's 32,000 men defeated the allied force of 50,000, leaving 20,000 dead. The losses of Philip are unknown but must have been severe, but the outcome was final. His son Alexander then only sixteen "is said to have been the first man that charge the Thebans' sacred band"[1] and fought in the battle as a commander of cavalry.
Encyclopedia of Military History, Dupuy & Dupuy, 1979