Afghanistan - Alexander and Greek Rule, 330 Ca. 150 B.C.

In the middle of the third century B.C., an independent, Greek-ruled state was declared in Bactria. Graeco-Bactrian rule spread until it included most of the territory from the Iranian deserts to the Ganges River and from Central Asia to the Arabian Sea by about 170 B.C. Graeco-Bactrian rule was eventually defeated by a combination of the internecine disputes that plagued Greek rulers to the west, the ambitious attempts to extend control into northern India, and the pressure of two groups of nomadic invaders from Central Asia--the Parthians and Sakas (perhaps the Scythians).

Upon Alexander's death in 323 B.C., his empire, which had never been politically consolidated, broke apart. His cavalry commander, Seleucus, took nominal control of the eastern lands and founded the Seleucid dynasty. Under the Seleucids, as under Alexander, Greek colonists and soldiers entered the region of the Hindu Kush, and many are believed to have remained. At the same time, the Mauryan Empire was developing in the northern part of the Indian subcontinent. It took control, thirty years after Alexander's death, of the southeasternmost areas of the Seleucid domains, including parts of present-day Afghanistan. The Mauryans introduced Indian culture, including Buddhism, to the area. With the Seleucids on one side and the Mauryans on the other, the people of the Hindu Kush were in what would become a familiar quandary in ancient as well as modern history--that is, caught between two empires.

Alexander and greek rule, 330-ca. 150 b.c.

It took Alexander only three years (from about 330-327 B.C.) to subdue the area that is now Afghanistan and the adjacent regions of the former Soviet Union. Moving eastward from the area of Herat, the Macedonian leader encountered fierce resistance from local rulers of what had been Iranian satraps. Although his expedition through Afghanistan was brief, he left behind a Hellenic cultural influence that lasted several centuries.

Afghanistan Alexander and Greek Rule, 330-ca. 150 B.C
Afghanistan - Mongabay.com
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Ancient history of Afghanistan - Wikipedia