Russian Empire

The Russian Empire from its proclamation by Peter the Great in 1721 until its dissolution in 1917 grew to become the third-largest empire in history at 22.8 million square kilometres, spanning 11 time zones from Poland to the Pacific. Its expansion across Siberia was one of the great geographic transformations of the modern era, and the Soviet Union that succeeded it — effectively its political heir — shaped the 20th century as decisively as any other force.