 Saint-Genis-Laval draws its name from Saint Genis or Genest, a Roman actor tortured under Diocletian.At the beginning of the 13th century, to differentiate it of other villages of the same name, the town added a qualitative to its name, «of the valley», which in the 15th century became "Laval".The first mention of the settlement of Saint-Genis dates back to 807, a year the archbishop Leidrade donated to the hospitals of Saint-Roman and Saint-Genis.