Charles Reuben Keyes (May 5, 1871 – July 23, 1951) was a pioneering American archaeologist and linguist based in Iowa, known as the founder of modern Iowa archaeology. He is, with (1857-1951), considered a key person to gaining protection for the Effigy Mounds National Monument, established by Congress in 1949 to protect hundreds of prehistoric earthworks built by indigenous Native American cultures.