To investigate the prevalence of diffuse idiopathic skeletal hyperostosis (DISH) in ancient populations.We studied 38 women and 61 men aged at least 30 years at death, whose remains were recovered from four cemeteries of the High Middle Ages (VIth to VIIIth century) located in Lorraine (eastern France). Criteria previously developed by Crubézy and Crubézy-Ibanez for paleopathological studies were used to determine whether the skeletal remains exhibited definite, possible, probable, or no DISH.Definite DISH with flowing ossification along the thoracic spine and ossification of peripheral enthesopathies was seen in 2.8 to 3.7% of the subjects from two cemeteries and in none from the other two cemeteries. Identical figures were found for possible DISH. The prevalence and male predominance s (nine of 13 subjects in any DISH category were males) were similar to those reported in contemporary studies and in other paleopathological studies.In the absence of clinical data on the metabolic status of the study subjects, our results suggest that DISH in our subjects was a marker for older age at death.