Born in 1530, Ivan IV (better known as Ivan the Terrible) became the Grand Prince of Moscow when he was only three, following his father's death by blood poisoning. At the age of 8, Ivan's mother died and the Boyar noblemen of Russia attempted to seige power from the young prince, but Ivan was able to stay. In 1547, age 16, he proclaimed himself the first Tsar of All Russia. During his reign, Russia conquered Khanates of Kazan, Astrakhan, and Siberia, transforming Russia into a multiethnic nation covering over one-and-a-half million square miles: and marking the first time Russia expanded east of the Ural Mountains.
However, after the death of his wife in 1560, Ivan grew more paranoid and allegedly, psychotic. From 1565-1572, Ivan launched the Oprichnina policies, which gave him a secret police that massacred thousands and destroyed many Russian towns to repress the population. In 1581, he beat his pregnant daughter-in-law for wearing immodest clothing, causing her to have a miscarriage. His son, also named Ivan, engaged in a heated argument with his father, which ended when Ivan struck his son in the head with a pointed staff (or a fireplace poker depending on the sources), causing his (accidental) death.
Ivan's mentality was highly abnormal and deteriorated throughout his life. Even as a child he was sadistic enough to torture animals and assault strangers. He personally tortured his prisoners and experimented with new methods of torture. His skeleton shows signs of mercury poisoning, which would have given him brain damage. He also had fused vertebrae, which would have given him constant back pains. He was a heavy alcoholic and obsessive with religion, even sleeping in cathedrals.
Ivan created the first Streltsy (Russian guardsmen armed with firearms) units sometime between 1545 and 1550. Ivan also created theOprichnina, an area in northern Russia where his henchmen, known as Oprichniki(who some historians write that Ivan's second wife Maria Temryukovna incited him to create)tortured and executed thousands of his enemies. Also from 1558–1583 he led one of the longest wars in human history, the Livonian War, which ended in failure for Russia. On March 28, 1584, Ivan the Terrible died of a stroke while playing chess. This left the kingdom in the hands of Ivan's other son, the unfit, mentally impaired and childless Feodor I. Fedor's weak reign and lack of heirs led to the Russian Troubles, a period of massive famine, civil war and instability.
The battle begins in a field with Ivan the Terrible knelt in a silent prayer, surrounded by 2 Russian Streltsy soldiers and 2 Oprichniki horsemen. He looks toward the sky, and then looks down to a bloodied prisoner tied to two horses, who is about to be quartered. Ivan smirks at the condemned as he rises from his kneeling position. Elsewhere, Hernán Cortés and 4 of his conquistadors are out for a ride when Cortés suddenly spots the group of men. The First Tsar of Russia nods to one of the hooded Oprichniki and the horsemen begin to pull. Ivan laughs at the prisoner's pain as Cortés, who has dismounted from horseback, shows concern and signals for his men to take position with their Arquebus rifle. Ivan immediately stops laughing when he notices the group of men aiming their firearms at his death squad. Cortés gives the signal with his sword and the conquistadors open fire. Before the gunmen fire, Ivan quickly grabs one of his soldiers and pulls him in front of him. The Russian is killed by the assault of bullets but the Terrible Tsar is knocked down to the ground by the force of the bullets.  As the Spanish riflemen hurry to reload their rifles, Ivan gets back to his feet and runs over to one of the horses, pulling the Oprichnik down.
Meanwhile, the last soldier sets up his Bardiche axe as a mount for his Pischal rifle, shooting and killing one of the Spaniards who shot the other soldier.  Ivan draws his Sablia and rides on, pulling the prisoner in half and dragging the torso behind him. The remaining soldier and the dismounted Oprichnik charge the Spaniards. The conquistadors calmly hold their ground as one of the Spaniards takes an Alabarda from his horse and hands it to Cortés. As the conquistadors continue to reload, Ivan rides up and slashes one of them in the face, killing him instantly.  He then changes course and rides to a retreating conquistador who has his Espada Ropera drawn and slashes him in the back of the neck, also killing him. 
Elsewhere, the mounted Oprichnik draws his Sablia and rides towards Cortés, who is still armed with his Alabarda. Cortés holds his ground and reaches with the poleaxe, pulling the hooded man down from horseback. Cortés then raises the poleaxe and brings it down into the Oprichnik's face.  The last Oprichnik charges at the head conquistador with his saber drawn. Cortés lifts the axe from the dead man's hood, parrying the sword and countering with a thrust attack, which impales the Oprichnik through the chest.  Cortés then calls for his horse, which the last mounted conquistador brings to him. The conquistador then rides on with his sword drawn. However, he is shot off his horse by the last soldier, who then finishes him off with a strike to the mid-section with his Bardiche while he is still down. 
Cortés then charges forth on his horse, slashing the Russian in the face with his Espada Ropera as he lifts the heavy Bardiche for a strike.  Ivan then spots Cortés and charges at him, sword raised. Ivan slashes Cortés as he rides by, but Cortés is unfazed as the saber bounces off his steel breastplate. After the charge is finished, Ivan notices that Cortés managed to cut him on his right cheek. Ivan gleefully licks the blood from his finger, then gives a shout as he and Cortés charge at each other, both men shouting. As the warriors ride past each other, Cortés ducks under Ivan's wild swing and thrusts his sword forward, puncturing Ivan's neck. Ivan slumps down in his saddle as he quickly bleeds out, then falls face down from his horse to the ground.  Hernán Cortés then walks up to the fallen Tsar, holding his right breast where the sword struck him and kicks Ivan to make sure that he's dead. Seeing no movement, Cortés holds his sword up and kneels down, taking the dead Tsar's money pouch and finding gold coins. Smiling at his spoils, Cortés stands up and raises his sword, shouting "¡Gloria!" (Glory) triumphantly.
Ivan's fascination with torture made him research the stories and history of Vlad the Impaler, who's legacy was still fresh at the time of Ivan's reign.
Ivan the Terrible is often said to have hade special “dens” in his castle for two or more bears and that the bears were deliberately underfed so that they would be more aggressive. Ivan would sometimes throw prisoners to the animals to be mauled to death as another intimidating form of execution. Ironically Ivan was known to hunt wild bears for sport.
According to the Ivan experts, Ivan considered himself as the Archangel Michael and considered it as his divine mission to bring down righteous vengeance on all those he saw as against God.
In addition to Quartering by horses, Ivan the Terrible was know to use other methods of torture such as impaling (which he did to the lover of his wife Vasilisa Melentyeva while she watched), drowning (which he did to his wife Maria Dolgorukaya after she cheated on him), public hanging, being buried alive and even roasting or frying his victims to death.
Ivan is the first warrior to use one of his men as a human shield. The first warrior to use a human shield in a simulated battle is one of the Yakuzas, who used an innocent bystander as a human shield.
Tsar is a title that translations to Caesar, meaning Ivan saw himself as the same position as a Roman Emperor.
Ivan is the only warrior featured in the show who has used chain mail armor that is accurate to historical examples, being the only mail shirt used so far with riveted links.