Alexander the Great was the son of Philip II of Macedon. His father was King and expanded the Macedonian empire as far as Thebes and Corinth before he was murdered.
Following his father's murder, Alexander took the throne in 336 BCE with dreams of glory. He would later be known as the greatest conqueror of the ancient world.
After taking Greece due to their weak condition following the wars with Persia, Alexander set his sights on conquering Persia as well. He sent his new Greek troops to do the job. In 334 he sent his troops to conquer Asia Minor. From there he advanced to the Holy Land and Egypt which he conquered within two years.
In this youtube video, we see how he advanced month by month and expanded his empire.
Expanding the empire was his legacy. He created the largest ancient civilization and that is what he is remembered for. Ruling the empire is another thing entirely.
Alexander only lived to be 33 years old. Shortly after his last campaign he fell ill and died. Following his death, his empire was divided by his generals as it was not stable.
Several famous generals, including Napoleon Bonaparte, have looked up to success in battle that Alexander the Great had.
However, One of his greatest successes was spreading his culture across such a large area. He created a common language and formed alliances with the Persians he conquered. All of the cultures within this region embraced and learned from one another. That was one incredible legacy to leave behind.