Who was the last president shot and killed?

George W. Bush; on May 10, 2005 in Freedom Square in Tbilisi, Georgia, a man named Vladimir Arutyunian lobbed a grenade towards the podium where Bush was standing and where the Georgian president, both countries' First Ladies, and various officials were seated. The grenade was a dud and didn't go off. Arutyunian was arrested in July of that year and convicted of the attempted assassinations, as well as the murder of a police officer while he was resisting arrest.