Muslim rule over Transoxania was consolidated a decade later when a Chinese-led army was defeated at the Battle of Talas in 751
The Russian Conquest of Central Asia took place in the second half of the nineteenth century. The land that became Russian Turkestan and later Soviet Central Asia is now divided between Kazakhstan in the north, Uzbekistan across the center, Kyrgyzstan in the east, Tajikistan in the southeast and Turkmenistan in the southwest. The area was called Turkestan because most of its inhabitants spoke Turkic languages with the exception of Tajikistan, which speaks an Iranian language.
The Persian-speaking Tajik minorities of Central Asia, who still form the majority of the population in the picturesque Silk Route cities of Samarkand and Bukhara, are living witnesses to the Iranian presence in the heart of Asia which dates back to prehistoric times.
The Sasanian Empire was the last kingdom of the Persian Empire before the rise of Islam and included parts of Turkmenistan, Uzbekistan, Tajikistan and Transoxiana. The Sasanian Empire during Late Antiquity is considered to have been one of Iran's most important and influential historical period