Trotsky was fatally attacked on Aug. 20, 1940.
When Joseph Stalin took over leadership of the Soviet Union after Vladimir Lenin's death, he saw Trotsky as potential threat to his authority and had him sent into exile.
Trotsky spent several years in Turkey, then moved to France and Norway before finally ending up in Mexico.
But even on the far side of the world, Trotsky couldn't escape his past. Most historians believe Stalin was responsible for sending the assassin who hacked him to death with an axe.