Five hundred and sixty intact skeletons and several thousand disarticulated vertebrae have been examined with special reference to spinal fusion. In period they ranged from a 21st dynasty Egyptian mummy to a mid-19th century skeleton. Osteophytes were found in about half of the specimens, as reported previously. Fifteen skeletons with extensive blocks of spinal fusion were also identified. Sacroiliitis was present in two, but the asymmetrical spinal disease and peripheral joint changes suggested Reiter's disease or psoriatic spondylitis rather than ankylosing spondylitis. The remaining 13 had typical features of Forrestier's disease, and extraspinal findings indicative of diffuse idiopathic skeletal hyperostosis (DISH) were also common. A review of the available literature suggests that many palaeopathological specimens previously reported as anklylosing spondylitis are examples of DISH or other seronegative spondylarthropathies. The antiquity and palaeopathology of AS needs reappraisal.