Vasili IV of Russia (Russian: Василий IV Иванович Шуйский, Vasíliy Ivánovich Shúyskiy, other transliterations: Vasily, Vasilii; 22 September 1552 – 12 September 1612) was Tsar of Russia between 1606 and 1610 after the murder of False Dmitriy I. His reign fell during the Time of Troubles. He was the only member of House of Shuysky to become Tsar and the last member of the Rurikid dynasty to rule.

He was a son of Ivan Andreyevich Shuisky. Born Prince Vasili Ivanovich Shuisky, he was descended from sovereign princes of Nizhny Novgorod and a 20th generation male line descendant of the Varangian prince Rurik. He was one of the leading boyars of Tsardom of Russia during the reigns of Feodor I and Boris Godunov. In all the court intrigues of the Time of Troubles, Vasily and his younger brother Dmitry Shuisky usually acted together and fought as one.

It was he who, in obedience to the secret orders of Tsar-to-be Boris, went to Uglich to inquire into the cause of the death of the Tsarevich Dmitry Ivanovich, the youngest son of Ivan the Terrible, who had perished there in mysterious circumstances. Shuisky reported that it was a case of suicide, though rumors abounded that the Tsarevich had been assassinated on the orders of the regent Boris Godunov. Some suspected that Dmitry escaped the assassination and that another boy was killed in his place, providing impetus for the repeated appearance of impostors (See False Dmitry I, False Dmitry II, and False Dmitry III). On the death of Boris, who had become tsar, and the accession of his son Feodor II, Shuisky went back upon his own words in order to gain favour with the pretender False Dmitriy I, who was attempting to gain the throne by impersonating the dead Tsarevich. Shuisky recognized the pretender as the "real" Dmitry despite having earlier determined the boy had committed suicide, thus bringing about the assassination of the young Feodor.

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