He legalized serfdom and was the first to use Siberia as a place of exile. 
He legalized serfdom and was the first to use Siberia as a place of exile. He became sole regent for his sister Irina's husband after the death of Nikita Yuriev. He was rumored to have ordered the murder of the Tsarevich Dmitri during the reign of Fyodor I Ivanovich. An advisor to Ivan the Terrible, he gained the throne after the death the heirless Fyodor. Later, his son, Tsar Fyodor II, was unable to defend the throne against the rebellion started by the Pseudo-Dmitri. FTP, identify this man who ruled Russia from 1598 to 1605, the subject of a famous drama by Pushkin and an opera by Mussorgsky.
He legalized serfdom and was the first to use Siberia as a place of exile.
Boris {Godunov}