Sigismund

Face and Hair: He possesses striking facial features, with a prominent nose and expressive eyes that convey his shrewd and authoritative nature. The historical nickname "Red Fox" (in Czech: liška ryšavá) refers to his red hair and beard, a characteristic maintained in his visual representation in the game.
Age and Stature: Depicted as a man in his 30s or 40s during the events of the game (historically he was around 35 years old in 1403), he possesses an athletic and imposing build, befitting a king who personally leads armies.
Combat Equipment: When in military attire, he wears a decorated cuirass, Augsburg-style plate shoulders, and a reinforced chainmail collar.
Civilian Attire: Outside of battles, he wears luxurious robes, such as the long Cuman caftan in shades of dark brown, reinforcing his connection with his Cuman mercenaries.

Sigismund of Luxembourg, son of Charles IV, was King of Hungary and Croatia from 1387, King of Germany from 1411, King of Bohemia from 1419, and King of Italy from 1431. He was also Prince of Silesia, Margrave of Lusatia from 1419, and, most notably, Holy Roman Emperor between 1433 and 1437.

From an early age, he was sent to study at the Hungarian court, where he quickly adapted to the harsh conditions of politics. Like other members of his family, he was kidnapped at least once (in this case, by the Hungarian nobility). Having lost faith in the Hungarian nobility, he turned his attention to Bohemia and came into conflict with his half-brother, Wenceslaus. Some Bohemian nobles welcomed Sigismund, hoping he would rid them of their ineffective monarch, while others allied themselves with Wenceslaus, resulting in long wars during which Sigismund and his Hungarian army (composed largely of Cuman mercenaries) repeatedly plundered Bohemia, often with the help of the Bohemian lords themselves – and especially Moravians. Sigismund fought not only to seize the throne from his brother but also against the Hussites, aiming to conquer the imperial crown.

Due to the continuous failures of King Wenceslas IV, who did not manage to live up to the reputation of his father Charles IV and preferred frivolous pursuits over political affairs, the Czech nobility looked for someone more suitable for the throne. Their choice fell on King Wenceslas' half-brother: King Sigismund of Hungary.

Sigismund opted for a radical solution: with the support of the nobility, he kidnapped King Wenceslas and forced him to abdicate, in order to gain the crown for himself. Then, at the head of a massive army composed mostly by Cuman mercenaries and commanded by his trusted general Sir Markvart von Aulitz, he invaded the kingdom of Bohemia, defeating all the nobles who remained loyal to Wenceslas.