The present-day country of Russia can easily be found on a world map due to its enormous land territory, largely thanks to the expansionist ambitions of Tsar Ivan the Terrible during the 16th century.  Ivan spurred the Russians to conquer and colonize Siberia, which was composed of the land east of the perilous Ural Mountains. It integrated the local tribes there with little difficulty due to their interest in trading.  By 1645 – just the span of a century – the borders of the Russian Empire reached the Pacific Ocean.