Modern Tajikistan fell under the rule of the Khanate of Bukhara during the 16th century and with the empire's collapse in the 18th century it came under the rule of both the Emirate of Bukhara and Khanate of Kokand. The Emirate of Bukhara remained intact until the 20th century but during the 19th century, for the second time in world history, a European power (the Russian Empire) began to conquer parts of the region.