When was 300 bc

The battle was hard-fought but Alexander's troops gained the upper hand, and killed or captured half of the Persian army which was forced to retreat. Alexander attacked the Persian infantry in the center of the lines and achieved an overwhelming victory, decimating the Persian forces. Nearly 1 million men faced an army of 50, Macedonians under Alexander. Alexander obtained excellent intelligence on the disposition of Persian forces and was able to attack the Persians, disrupting their lines which resulted in a general Persian retreat.

Darius fled the battlefield, was pursued and was eventually assassinated in Bactaria. It is considered part of the Classical era, epoch, or historical period. In the Mediterranean Basin, the first few decades of this century were characterized by a balance of power between the Greek Hellenistic kingdoms in the east, and the great mercantile power of Carthage in the west.

This balance was shattered when conflict arose between ancient Carthage and the Roman Republic. In the following decades, the Carthaginian Republic was first humbled and then destroyed by the Romans in the First and Second Punic Wars. In the eastern Mediterranean, the Seleucid Empire and Ptolemaic Kingdom, successor states to the empire of Alexander the Great, fought a series of Syrian Wars for control over the Levant.

In mainland Greece, the short-lived Antipatrid dynasty of Macedon was overthrown and replaced by the Antigonid dynasty in BC, a royal house that would dominate the affairs of Hellenistic Greece for roughly a century until the stalemate of the First Macedonian War against Rome.

Macedon would also lose the Cretan War against the Greek city-state of Rhodes and its allies. In India, Ashoka ruled the Maurya Empire. He captured Babylon and Susa along the way, amassing much spoils. A revolt at home forced Ptolemy to return to Egypt. He also successfully calculated the area of a circle. Thus Roman rule was extended even farther. He caluculated the size of the earth, sun and the moon. He showed that the earth orbited the sun and the moon orbited the earth.

When Rome provoked Carthage by encouraging a rebellion in one of its colonies -- Spain -- Carthage struck back. Led by its greatest general Hannibal, Carthage was determined to bring war to Rome. Hannibal crossed the Alps with between 30, and 40, men, 6, horses and even elephants.