What was different about the Russian Empire from other European empires?

Unlike other European empires, the Russian empire was contained on a single landmass. The Russians invaded and controlled lands that were pretty close to home base. Other empires - like the British, the Portuguese, and the French - were all overseas. The British, Spanish, and French empires had lands in the Americas.

The Portuguese and British empires had land in China. Russia, on the other hand, invaded places like the Ukraine, Yugoslavia, Czechoslovakia, and other places near their borders. It was considered a land buffer during World War II between the Russian empire and Hitler’s dangerously close army. Other than this single difference, the Russian empire was pretty much the same as the other European empires. Their colonies eventually pulled away as well, and left the Russian border as we know it today.