This is the face of cruellest man who boiled his subjects alive nearly 440 years ago

Kings and monarchs have been known for committing atrocities, killing people and being ruthless in nature.

However, Russia's first tsar - Ivan the Terrible - has etched another kind of arc in history where he has been found to be the cruellest tyrant to have existed on Earth 440 years ago.

To understand how he actually looked and how cold his gaze was,scientists have now reconstructed his face using his skull.

All about Ivan the Terrible

Russia's first tsar Ivan the Terrible, in his rule, expanded his empire and transformed his country.

However, he is remembered for his barbarity and for cruelly treating his subjects by boiling them alive or roasting and impaling them, getting them torn apart by horses and drowning them under the ice.

He is even believed to have beaten his own son to death, after he confronted him for hitting the prince's pregnant wife which led to her miscarriage.

However, the true face of the tsar was lost in history and now his face has been reconstructed to understand how he actually looked.

In 1963, the grave of the tsar was excavated by Soviet scientist Mikhail Gerasimov.

The work's lead author Cicero Moraes said, "According to Dr Gerasimov's study, it appears that Ivan indulged in a disorderly life of excessive eating and alcohol abuse."

"This must have worsened his condition in his last years. This is in contrast to the appearance he had when younger, when he was described as tall, with beautiful hair, broad shoulders, strong muscles, and a pleasant face," he added.

"An interesting fact is that they found a large amount of mercury in his body, which made some suspect poisoning. But given the habits of the time, it may have been used as a treatment for some health problem," Moraes further added.

How the face was reconstructed?

Several approaches were combined to reconstruct the final face. In one method, data from living donors was used to understand the likely thickness of the skin of the tsar on his skull.

Another technique put to work was anatomical deformation, in which a living donor's face and skull were digitally altered till they matched the dimensions of Ivan the Terrible.

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"The final bust was a combination of all this data," said Moraes, who is a Brazilian graphics expert. He said it has a "strong and determined" likeness.

"It was a very interesting experience, as it involved not only facial approximation, but the study of the tsar's history," Moraes added.

(With inputs from agencies)