Why was Ivan the fourth called the Terrible?

Answer 1

All the answers below are inaccurate. Ivan the Terrible was called that for his reputation as being a cunning and formidable military leader. This title was given to him at an early age after the conquest of a powerful and important Tartar city in which he successfully mined under the city walls and used gun powder to breach them. He was able to vanquish an army far larger than his during that campaign. "Terrible" was meant as an acknowledgment of his military prowess rather than for any cruel or sadistic deeds he may have done. The irony is he did gradually become terrible as he got older but this was brought on by slow Mercury poisoning that was in the medication he took for his chronic and painfully debilitating Arthritis.

Ivan the Terrible was named Grand Prince of Moscow in 1533 and the crowned Czar in 1547. His rule went from 1533-1580. Ivan the Terrible often had fits of rage in his younger age due to the fear of being murdered by thoses wanting to take the throne. This often led to the paranoia he would later develop. He's called terrible due to the fact that he had a certain lust for power. He reduced the power of boyars greatly, and peasants weren't treated any nicer. He created a secret police which would cause terror in the country. He also was said to have beaten his pregnant daughter-in-law, causing a miscarriage. His son, also called Ivan, got into a heated argument, which led to his father taking his pointed staff and striking him with it on November 16, 1581. This blow proved fatal, leaving Ivan the terrible devastated but not enough to stray from his path to absolute power.

Answer 2

He inspired fear in those he ruled.