Guillain-Barré syndrome (GBS) is a heterogeneous group of acute immune-mediated neuropathies, including acute inflammatory demyelinating polyneuropathy (AIDP) and acute motor axonal neuropathy (AMAN). AMAN is an axonal subtype of GBS that has been known since the 1990s; this term was first used to describe a summer epidemic of acute ascending paralysis observed in children in northern China (and Mexico). It is pathologically characterized by noninflammatory axonal degeneration of the motor nerves (with little or no demyelination). The French neurologist Jules Dejerine (1849–1917) conducted a clinical and pathologic description of AMAN in the late 19th century. We describe his observations, which provide us with valuable information on the course of pathologic lesions in this disease.