town, Puy-de-Dome departement, Auvergne region, central France. It lies along the Ambene River at the western edge of the fertile Limagne Plain, just north of Clermont-Ferrand. The old town, built around the ancient Church of Saint-Amable, is ringed by the wide boulevards that replaced its former ramparts. In the European Middle Ages, Riom was the capital of the county of Auvergne. It continued to be the seat of the judiciary when Auvergne came under French sovereignty. During the German occupation in World War II, a supreme court of justice was set up by the Vichy government at Riom. In a noted incident in the annals of French justice, the court tried Edouard Daladier, Paul Reynaud, and Leon Blum, premiers of the Third Republic, and General Maurice Gamelin for responsibility for the defeat of France. Tobacco products and pharmaceuticals are manufactured. Pop. (1982) 17,626.
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