Sigismund

Sigismund was the First Captain of the Imperial Fists Legion during the Great Crusade and would go on to become the first High Marshal of the Black Templars Space Marine Chapter after the Second Founding in the early 31st Millennium.

History
Sigismund served beside the Imperial Fists Legion's Primarch Rogal Dorn himself, and would fight throughout the entire Great Crusade. Famously brash and headstrong, he had a strong tendency to attack the enemy, no matter the danger or previous mission he had been sent to accomplish. This might have been a problem if he had not been such a superb warrior who could defeat almost any opponent. He was present when Dorn learned of his brother Horus's treachery, being Dorn's closest advisor and most trusted lieutenant, and was the first Champion of the Imperial Fists.

Champion Sigismund, First Captain of the Imperial Fists Legion, was chosen by his Primarch as the first High Marshal of the newly created Black Templars Chapter during the Second Founding. The Chapter took upon themselves the black and white panoply of his personal heraldry. Chosen as the Emperor's Champion for his fervent faith in the Emperor and his undying devotion to Mankind, those zealous warriors who became Black Templars sought to emulate his heroic example. Seeing the strife that beset the Legiones Astartes during the days of the Second Founding, he determined that a gesture of supreme faith was needed. As High Marshal of the Black Templars, Sigismund swore a mighty oath that upon leaving Terra, he would prove his loyalty, never resting in the prosecution of his duties against the enemies of the Emperor. It is an oath that every subsequent High Marshal has renewed, and so the greatest and longest Space Marine Crusade in Imperial history was begun, a Crusade that has continued unbroken for ten thousand Terran years.