In what way did the Mongol empire affect Russia and Persia similarly?

The Mongol Empire had a devastating affect on Persia or modern day Iran. Today, Genghis Khan, the leader of the Mongol horde, is known as a genocidal warlord which killed millions of people there. A similar thing happened when the Mongols first invaded Russia as they slaughtered entire cities during their invasions; an example being the city of Kiev.