Who gave Ivan the nickname the terrible?

Ivan IV of Russia, commonly known as Ivan the Terrible, received the nickname due to his reign marked by extreme cruelty and violent actions, particularly during the Oprichnina period. The term "Terrible" in this context is derived from the Russian Word "grozny," which can mean "awe-inspiring" or "formidable," rather than simply "terrible." His harsh policies and brutal tactics, including the repression of nobility and the infamous massacre of Novgorod, contributed to this fearsome reputation.