Vladimir Putin
Vladimir Putin has been the Russian president, or effectively the president, for as long as anyone can now remember. Known for murdering dissidents and invading neighboring states, he was also, in a very different time (2003), one of the first invited guests to Columbia's World Leaders Forum.
His visit was truly bizarre and unthinkable by today's standards, featuring Russian snipers posed in John Jay bathrooms to secure the Morningside Heights campus for his visit and Putin's enjoyment of some baseball skills from nearby Harlem youth on South Lawn. Hundreds of students gathered along campus pathways to watch him swagger around like he owned the place, too.