The ancient empire known for its military strategies and phalanx formation was the Macedonian Empire, particularly under the leadership of King Philip II and his son Alexander the Great. The phalanx was a military formation that arranged soldiers in tightly packed rows, working in unison to create a formidable front. This strategy allowed for both offense and defense, enhancing the effectiveness of troops in battle. Under Alexander, the Macedonian army expanded its reach, conquering vast territories and spreading Greek culture. Alexander's tactics and strategies revolutionized warfare and had a lasting impact on military theory and practice.