Russian Empire census
The Russian Empire census, formally the First general census of the population of the Russian Empire in 1897, was the first and only nation-wide census performed in the Russian Empire. The census recorded demographic data as of 9 February 1897 [O.S. 28 January]; with a population of 125,640,021, it made Russia the world's third-most populated country at the time, after the British and Qing empires.