This is the Varangian Guard

The Varangian Guard was an elite unit in the Byzantine Empire, renowned for its fierce warriors and unparalleled loyalty. Originally composed of Norsemen—predominantly from Scandinavia—the Guard came into existence in the late 10th century under Emperor Basil II. 

The Varangian Guard was active primarily between the late 10th century and the early 14th century. They were first established around 988 AD, when Byzantine Emperor Basil II invited Norse warriors, including those from Kievan Rus, to serve as his loyal elite force. Their prominence lasted for several centuries, though their influence and numbers gradually diminished after the 1204 sack of Constantinople during the Fourth Crusade. By the 14th century, the Guard had largely faded from historical significance. Over time, its ranks expanded to include warriors from Kievan Rus and other regions in Eastern Europe.

These formidable fighters served as personal protectors to the Byzantine emperors, tasked with guarding the imperial palace and accompanying the emperor during military campaigns. Distinguished by their unwavering dedication and fearlessness in battle, the Varangians wielded their iconic weapons, such as massive axes, with deadly precision.

The Guard's reputation extended far beyond the empire's borders, immortalized as a symbol of strength, loyalty, and exoticism in medieval history. Their legacy endures as a testament to the cultural exchanges and alliances between the Byzantine Empire and the Norse world.