Page "History of Tajikistan" Paragraph 8

After the Persian Empire was defeated by Alexander the Great, Bactria, Sogdiana and Merv, being part of Persian Empire, had to defend themselves from new invaders.

In fact, the Macedonians faced very stiff resistance under the leadership of Sogdian ruler Spitamenes.

Alexander the Great managed to marry Roxana, the daughter of a local ruler, and inherited his land.

Following Alexander's brief occupation, the Hellenistic successor states of the Seleucids and Greco-Bactrians controlled the area for another 200 years in what is known as the Greco-Bactrian Kingdom.

During the time period from 90 BC to 30 BC, Yuezhi destroyed the last Hellenistic successor states and, together with the Tocharians, ( to whom they were closely related ) created a Kushan Empire around 30 AD.