Background Numerous hypotheses on the cause of Napoleon Bonaparte's death have been proposed, including hereditary gastric cancer, arsenic poisoning, and inappropriate medical treatment. We aimed to determine the etiology and pathogenesis of Napoleon's illness by a comparison of historical information with current clinicopathologic knowledge.

Investigations Evaluation of Napoleon's clinical history, original autopsy reports, and of historical documents. The clinicopathologic data from 135 gastric cancer patients were used for comparison with the data available on Napoleon.

Diagnosis At least T3N1M0 (stage IIIA) gastric cancer. Napoleon's tumor extended from the cardia to the pylorus (>10 cm) without infiltration of adjacent structures, which provides strong evidence for at least stage T3. The N1 stage was determined by the presence of several enlarged and hardened regional (perigastric) lymph nodes, and the M0 stage by the absence of distant metastasis. Analysis of the available historical documents indicates that Napoleon's main risk factor might have been Helicobacter pylori infection rather than a familial predisposition.

Conclusions Our analysis suggests that Napoleon's illness was a sporadic gastric carcinoma of advanced stage. Patients with such tumors have a notoriously poor prognosis.