of the earthworks. In his book, Antiquities Discovered in the Western States (1820), Atwater claimed that "Indian remains" were always found right beneath the surface of the earth, while artifacts associated with the Mound Builders were found fairly deep in the ground.Atwater argued that they must be from a different group of people. The discovery of metal artifacts further convinced people that the Mound Builders were not identical to the Southeast Woodland Native Americans of the 18th century. It is now thought that the most likely bearers of the Plaquemine culture, a late variant of the Mississippian culture, were ancestral to the related Natchez and Taensa peoples. The Natchez language is a language isolate. The Natchez are known to have historically occupied the Lower Mississippi Valley. They are first mentioned in French sources of around 1700, when they were centered around the Grand Village close to present day Natchez, Mississippi. In 1729 the Natchez revolted, and massacred the French colony of Fort Rosalie. The French retaliated by destroying all the Natchez villages. The remaining Natchez fled in scattered bands to live among the Chickasaw, Creek and Cherokee peoples. They traveled with them on the trail of tears when federal Indian removal policies after 1830 forced the Native Americans out of the Southeast and west of the Mississippi River to Indian Territory (admitted in the early 20th century as the state of Oklahoma. The Natchez language became extinct in the 20th century, with the death in 1957 of the last known native speaker, Nancy Raven. Maps Popular mythology Alternative scenarios and hoaxes Based on the idea that the origins of the mound builders lay with a mysterious ancient people, there were various other suggestions belonging to the more general genre of Pre-Columbian trans-oceanic contact theories, specifically involving Vikings, Atlantis, and the Ten Lost Tribes of Israel, summarised by Feder (2006) under the heading of "The Myth of a Vanished Race". Benjamin Smith Barton in his Observations on Some Parts of Natural History (1787) proposed the theory that the Mound Builders were associated with "Danes", i.e. with the Norse colonization of North America. In 1797, Barton reconsidered his position and correctly identified the mounds as part of indigenous prehistory. Notable for the association with the Ten Lost Tribes is the Book of Mormon (1830). In this narrative, the Jaredites (3000–2000 BCE) and an Israelite group in 590 BCE (termed Nephites, Lamanites, and