Diagnosing scurvy (vitamin C deficiency) in adult skeletal remains is difficult despite documentary evidence of its past prevalence. Analysis of 20 European colonists buried at Saint Croix Island in New France during the winter of 1604-1605, accompanied by their leader Samuel de Champlain's eyewitness account of their symptoms, provided the opportunity to document lesions of adult scurvy within a tightly dated historical context. Previous diagnoses of adult scurvy have relied predominantly on the presence of periosteal lesions of the lower limbs and excessive antemortem tooth loss. Our analysis suggests that, when observed together, reactive lesions of the oral cavity associated with palatal inflammation and bilateral lesions at the mastication muscle attachment sites support the differential diagnosis of adult scurvy. Antemortem loss of the anterior teeth, however, is not a reliable diagnostic indicator. Employing a biocultural interpretive approach, analysis of these early colonists' skeletal remains enhances current understanding of the methods that medical practitioners used to treat the disorder during the Age of Discovery, performing rudimentary oral surgery and autopsies. Although limited by a small sample and taphonomic effects, this analysis strongly supports the use of weighted paleopathological criteria to diagnose adult scurvy based on the co-occurrence of specific porotic lesions.