Tabes dorsalis, a late neurological complication of syphilis, is nowadays almost extinct. The path to understanding this disease and its pathophysiology was long and winding, spanning multiple centuries. The 19^th century was a crucial period for understanding it. In the first third of the century, German and French physicians defined the semiology of tabes dorsalis, renamed in France “ataxie locomotrice progressive [progressive locomotor ataxia].” Nevertheless, the multiplicity of ancient and recent terms and the description of sometimes unclear nosological concepts (tabes nervosa, tabes spasmodic, nervo-tabes, etc.) were a hindrance to understanding it. Tabes dorsalis was a fertile ground for the description of many clinical signs that have become classics in medicine. No real treatment was available and various unusual therapies were performed. For a long time, the etiology of this disease remained unknown. The link between syphilis and tabes dorsalis was slowly established in the second part of the 19^th century from epidemiologic observations. We present an overview of the concept of tabes dorsalis in the medical context of the 19^th century and discuss the medical observations of some famous patients suffering from the disease such as Édouard Manet (1832–1883) and Alphonse Daudet (1840–1897).