What Russian figure was assassinated by Ramon Mercader in 1940?

The Russian revolutionary Leon Trotsky was assassinated by Ramón Mercader in 1940. Mercader, a Spanish-born NKVD agent operating under an assumed identity, attacked Trotsky at his home in Coyoacán, Mexico City, on August 20, 1940.

Mercader used a mountaineering ice axe, striking Trotsky in the head while pretending to show him a document. The injury was not immediately fatal: Trotsky struggled with his attacker and told his guards not to kill Mercader, hoping he could be questioned. Trotsky died in a hospital the following day from his wounds.

Trotsky had been a major figure in the Russian Revolution and later became a fierce opponent of Joseph Stalin. Mercader was convicted under the false name Jacques Mornard and spent 20 years in a Mexican prison. After his release, he moved to the Soviet Union and was secretly honored by the state for the killing.