* The Russian Empire: This included all the territories ruled by the Tsar, and the population is estimated to be around 170 million people.
* The European part of Russia: This refers specifically to the European territories of the Russian Empire, excluding territories like Siberia, Central Asia, and the Caucasus. The population of this region is estimated to be around 100 million people.
It's important to note that these are estimates, and the actual population could have varied depending on the source and methodology used.