Original: The first fossils named Edmontosaurus were discovered in southern Alberta, Canada, in what used to be called the lower Edmonton Formation. The type species, E. regalis, was named by Lawrence Lambe in 1917, although several other species that are now classified in Edmontosaurus were named earlier.
Simplified: Edmontosaurus was named by Lawrence M. Lambe in 1917 from a fossil found in Edmonton Rock Formation, in Alberta, Canada.