Alexander the Great

The interaction between Hellenistic Greece and Buddhism began when Alexander the Great conquered Asia Minor and the Achaemenid Empire, reaching the north west frontiers of the Indian subcontinent in 334 BC. There, he defeated King Puru in the Battle of the Hydaspes (near modern-day Jhelum, Pakistan) and conquered much of the Punjab. However, Alexander's troops refused to go beyond the Beas river, and he was forced to march his army southwest.
Alexander created garrisons for his troops in his new territories, and founded several cities in the areas of the Oxus, Arachosia, and Bactria, and Macedonian/Greek settlements in Gandhara and the Punjab. The regions included the Khyber Pass - a geographical passageway south of the Himalayas and the Hindu Kush mountains - and the Bolan Pass, on a trade route connecting Drangiana, Arachosia and other Persian and Central Asian kingdoms to the lower Indus plain. It is through these regions that most of the interaction between South Asia and Central Asia took place, generating intense cultural exchange and trade.