The Russian Empire was a large empire stretching, at its height, from Eastern Europe to the ends of Siberia. The Empire fell apart during the Russian Civil War, which followed the Second Russo-Japanese War.
Its territory at dissolution included the following nations (provisional and incomplete list)
- Komi Republic
- Muscovite Soviet Socialist Republic
- Poland (part)
- Kingdom of St. Petersburg
In addition, Japan's Karafuto Prefecture was part of Russia at its collapse, and the Kingdom of Alaska had been Russian until 1887