Kalagann, also known as Kalagann of Ursh, was a despot and techno-barbarian warlord of Old Earth, who ruled over the nation-state of Ursh during the late Age of Strife. His exploits were well-documented in the annals of Ursh, a nation located on the steppes of what had once been Central Asia, Russia and Siberia. These records were collectively known as the Chronicles of Ursh. Kalagann was eventually overthrown and slain during the early campaigns of the Unification Wars by the Emperor of Mankind and His genetically-enhanced Thunder Warriors.
To those of the burgeoning Imperium of Man raised on the tenets of the Imperial Truth, the apocryphal tales and depictions of war in that period of Old Night were considered grandiose and outrageous, and were held by many later Imperial Iterators to be outright nonsense, due to talk about "daemons" and "magick". Despite the grandiloquent language and style of the Chronicles of Ursh, many Imperial scholars later came to consider it a classic work of human literature that provided valuable insight into this pre-Unification state's rise and the wars of the Ursh against the equally techno-barbarian Nordafrik Conclaves.
The Chronicles of Ursh spoke of Kalagann's many cruel practices, which matched his equally cruel character. During the era of Old Night, long forgotten cities were routinely sacked or burned or evaporated in nuclear storms. The seas were constantly stained with blood and the land was carpeted with the numberless bleached bones of the conquered. When armies marched, they marched a billion strong, the banners of a million standards swaying in the atomic winds. The battles that took place were a stupendous maelstrom of blades, black helms, and horns lit by the fire of cannons and burners. Kalagann was said to have had three great generals: Lurtois, Sheng Khal (also known as Shang Khal) and Quallodon, who crafted for Kalagann an impossibly vast domain. The description of Kalagann's generals in the Chronicles was similar to those later used to describe the Primarchs of the Emperor of Mankind.
The Chronicles of Ursh narrated, in great detail, how Kalagann and his techno-barbarian armies were able to accomplish feats-of-arms that no pre-Unity warriors should have been capable of unleashing. This was particularly true since the armies of Ursh consisted mostly of genetically unaltered human soldiers. But Kalagann also employed powerful psykers within his armies, using their arcane abilities to unleash the foul powers of the Warp upon his enemies, including the Imperial forces when the Unification Wars began. Also, it was said that the sorcerous powers of Kalagann mentioned in the Chronicles of Ursh comprised the main component of Ursh's military power. It was to face such unholy power that the Emperor knew He needed to create genetically engineered, transhuman supersoldiers who were partially resistant to psychic powers when He began His quest to unify Mankind's homeworld.
Due to the nature of Ursh's sorcerous armies, the Chaos Gods were likely the powers behind the throne of Ursh, and Kalagann was merely one of their many puppets during the Age of Strife, manipulated into doing their bidding. Despite their apparent influence and favour, the Dark Gods failed to save Kalagann when he faced the proto-Astartes of the Thunder Legion in service to the ascendant Emperor of Mankind. The Thunder Warriors, led by the Emperor, eventually defeated the armies of Ursh and slew Kalagann, one of the first notable victories of the Imperium during the long campaign to unify Terra.
At the time of the Horus Heresy in the early 31st Millennium, Kalagann's distinctive suit of Artificer Armour, known as the Armour of Pearl, was kept as a trophy in the vestibule of the Eternity Gate in the Imperial Palace.