From about 500 BC, most of Central Asia was under Persian
control or influence. Bactria (today thought to be Balkh in Northern
Afghanistan) on the banks of the Oxus (now known as the Amu Darya)
was the center of Persian civilization in Eastern Iran. The Persians
displaced the Scythian and Cimmerian nomadic tribes in the region.
Afrosiab (now Samarcand) was the centre of the region known as Sogdiana
that covered what is today Southern Uzbekistan and much of Tajikistan.
The cities of Samarcand and Boukhara, although today in the territory
of Uzbekistan, are centres of Tajik/Persian culture.
Alexander of Macedonia defeated the armies of the Persian
Emperor Darius II between 336-323 BC and brought about the fall
of the Achaemenid Empire. Alexander subjugated Sogdiana but, in
order to promote the pacification of the conquered peoples, married
Roxane, daughter of a local chieftain. When Alexander died in 323
BC, the Macedonian Empire broke up. After a long period during which
Bactria was ruled by Graeco-Macedonian satraps and subjected to
frequent invasions by nomadic Turkic hordes, the area fell under
the control of the Yuchi from what is now the Gansu region in Western
China (Kushan Empire) from the second century BC to the third century
The Persian Sasanids (224-642 AD) destroyed the Kushan Empire and
the region reverted to Persian control.