8. Ivan the Terrible
Ivan the Terrible or Ivan IV Vasilyevich was a Russian tsar and considered as an early founder of the modern Russia. His most important contributions were the conquest of Siberia, centralization of power and the creation of new legal code. His most violent act was the Sack of Novgorod, when he suspected that the city was planning to defect to Poland. He built a wall around the city and each day, his troops rounded 1500 people randomly from the city to be massacred. He killed his own son in a heated argument after Ivan struck his pregnant daughter-of-law who was accused of wearing immodest clothing.