We offer here an observation written in 1866 by Jean-Martin Charcot, accompanied by drawings made during the autopsy of a patient who died of "cerebral softening." Focusing mainly on French medical progress at the time, our survey of the state of knowledge of cerebrovascular pathology indicates that Charcot completely explained the pathophysiology of cerebral infarction, describing the ulceration of an atheromatous plaque at the intima of an artery, on which a clot aggregates, blocks the vessel, or releases embolus downstream, causing cerebral ischemia and parenchymal lesions. Using the term "cholestérine" (cholesterin), the name of cholesterol at the time, he identified the biological nature of atheromatous plaques, and made detailed drawings. This observation, included in the famous thesis of Ivan Poumeau, indicates that Charcot did not neglect cerebrovascular pathology, ischemic in this case, but also pathology caused by hemorrhaging, as in the thesis of Charles Bouchard. This interest, which we see clearly during his first decade at Hôpital de la Salpêtrière, gradually turned toward other neurological pathologies that ensured his fame as a founder of neurology more enduringly and overshadowed the conceptual advances he made in the vascular domain.