Why were Dracula's actions attributed to Ivan the Terrible?

‘The Tale of Dracula’ was well known in Old Russia. Some historians suggest that its author, clerk Fyodor Kuritsyn, made a free translation of a European pamphlet as early as the late 15th century. Subsequently, some of Dracula's traits and actions began to be attributed to Ivan the Terrible, who reigned later.

Many such stories were recounted in his book ‘The Present State of Russia’ by British physician Samuel Collins, who served at the Moscow court from 1659 to 1666. One of the stories recounts how Ivan the Terrible, while receiving the French ambassador, ordered his hat to be nailed to his head for not removing it in front of the tsar. This eerie plot has a specific literary "ancestor" – ‘The Tale of Dracula’, which contains an episode in which the hero treats Turkish ambassadors in exactly the same way:

"One day, ambassadors came to him from the Turkish king… and entered according to their custom, bowed, but did not remove their caps from their heads. He asked them: 'Why did you do this? You came to the great sovereign and brought such dishonor upon me?' They replied: 'Such is the custom, sovereign, in our land.' He said to them: 'And I wish to confirm your law to you, so that you adhere to it firmly'… and ordered their caps to be nailed to their heads with iron nails…"

In other words, the story of the ambassador's punishment for his covered head from ‘The Tale of Dracula’ (late 15th century) began to be attributed in oral tradition to Ivan the Terrible (16th century) and was then was most likely recorded by Collins in the 17th century as a true story. Since both the Wallachian ruler and the Russian tsar had a reputation in popular tradition as being cruel rulers.