Transoxiana or Transoxania is the Latin name for the region and civilization located in lower Central Asia roughly corresponding to eastern Uzbekistan, western Tajikistan, southern Kyrgyzstan and parts of southern Kazakhstan, and of Turkmenistan. The name was coined by Alexander the Great in the 4th century BC when Alexander's troops conquered the region. The region may have had a similar Greek name in Alexander's time, but the earlier name is no longer known. Geographically, it is the region between the rivers Amu Darya to its south and the Syr Darya to its north.