In October 2024, an archaeological excavation at Hasenleitengasse in Vienna, Austria, uncovered a Roman-period mass grave with at least 128 individuals. Radiocarbon dates and few available finds date the feature to the late 1st to early 2nd centuries CE. This study presents a first bioarchaeological assessment of the trauma observed in the individuals from Hasenleitengasse. The disorganised burial situation with intertwined individuals in multiple orientations suggests that the deceased were interred with a lack of care or under time pressure. Bioarchaeological analysis determined that all individuals, whose sex could be estimated were biologically male, with an estimated age-at-death ranging from 20 to 35 years. Forty-eight individuals exhibited various forms of trauma, suggesting a violent cause of death. Of the individuals with traumatic lesions, 85% had instances of perimortem trauma. The types of documented perimortem trauma include sharp force, blunt force, and projectile injuries. Most of the sharp force trauma was observed on the skull with the highest prevalence of trauma was seen on and around the pelvis (40%). The diversity of traumatic perimortem lesions indicates a violent mass fatality. Expansionist warfare, internal conflicts, and the integration of diverse populations created complex expressions of identity during the Roman period. Although warfare in the Roman period is well documented in historical sources, physical evidence of war-related events has been exceedingly rare. The mass grave from Hasenleitengasse, thus represents a unique source of data allowing first-hand insights into life and death of Roman-period combatants.