Detailed Instructions: In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Q: This ruler conquered the Khanates of Kazan and Astrakhan before fighting the Livonian War. An organization created by this ruler was headed by Malyuta Skuratov and perpetrated the Novgorod Massacre. This man used the Oprichniki to crush the power of the boyars. This man called the first [*] zemsky sobor parliament, and he supposedly blinded the architect of St. Basil's Cathedral. After this man killed his son Ivan Ivanovich, the mentally retarded Feodor I became his heir, leading to the Time of Troubles. For 10 points, name this first of the Rurik Tsars of Russia, known for his extreme cruelty.
A:
History