William M Denevan, noted author and Professor Emeritus of Geography at the University of Wisconsin-Madison, said on this subject in his essay "The Pristine Myth: The Landscape of the Americas in 1492"; "The decline of native American populations was rapid and severe, probably the greatest demographic disaster ever. In many regions, particularly the tropical lowlands, populations fell by 90 percent or more in the first century after the contact." Estimates of the pre-Columbian population of what today constitutes the U. vary significantly, ranging from William M Denevan's 3.8 million in his 1992 work The Native Population of the Americas in 1492, to 18 million in Henry F Dobyns's Their Number Become Thinned (1983). or forced) became a consistent policy through American administrations.As most Native American groups had historically preserved their histories by oral traditions and artwork, the first written sources of the conflict were written by Europeans.At the time of the first contact, the indigenous cultures were quite different from those of the proto-industrial and mostly Christian immigrants.The pre-Columbian era incorporates all period subdivisions in the history and prehistory of the Americas before the appearance of significant European influences on the American continents, spanning the time of the original settlement in the Upper Paleolithic period to European colonization during the Early Modern period.While technically referring to the era before Christopher Columbus' voyages of 1492 to 1504, in practice the term usually includes the history of American indigenous cultures until they were conquered or significantly influenced by Europeans, even if this happened decades or even centuries after Columbus' initial landing.Even before the European settlement of what is now the United States, Native Americans suffered high fatalities from contact with new European diseases, to which they had not yet acquired immunity; the diseases were endemic to the Spanish and other Europeans, and spread by direct contact and likely through pigs that escaped from expeditions.Smallpox epidemics are thought to have caused the greatest loss of life for indigenous populations.
There are over 500 federally recognized tribes within the US, about half of which are associated with Indian reservations.They carried out resistance against United States incursion in the decades after the end of the Civil War and the completion of the Transcontinental Railroad in a series of Indian Wars, which were frequent up until the 1890s and continued into the 20th century. Indian agents encouraged Native Americans to adopt European-style farming and similar pursuits, but European-American agricultural technology of the time was inadequate for the often dry reservation lands, leading to mass starvation. The terms used to refer to Native Americans have at times been controversial.Over time, the United States forced a series of treaties and land cessions by the tribes and established reservations for them in many western states. The ways Native Americans refer to themselves vary by region and generation, with many older Native Americans self-identifying as "Indians" or "American Indians", while younger Native Americans often identify as "Indigenous" or "Aboriginal".It is not definitively known how or when the Native Americans first settled the Americas and the present-day United States.The prevailing theory proposes that people migrated from Eurasia across Beringia, a land bridge that connected Siberia to present-day Alaska during the Ice Age, and then spread southward throughout the Americas over the subsequent generations.As American expansion reached into the West, settler and miner migrants came into increasing conflict with the Great Basin, Great Plains, and other Western tribes. Contemporary Native Americans have a unique relationship with the United States because they may be members of nations, tribes, or bands with sovereignty and treaty rights.These were complex nomadic cultures based on (introduced) horse culture and seasonal bison hunting. Cultural activism since the late 1960s has increased political participation and led to an expansion of efforts to teach and preserve indigenous languages for younger generations and to establish a greater cultural infrastructure: Native Americans have founded independent newspapers and online media, recently including First Nations Experience, the first Native American television channel; established Native American studies programs, tribal schools, and universities, and museums and language programs; and have increasingly been published as authors in numerous genres.Genetic evidence suggests at least three waves of migrants arrived from Asia, with the first occurring at least 15 thousand years ago.These early inhabitants, called Paleoamericans, soon diversified into many hundreds of culturally distinct nations and tribes.A vast variety of peoples, societies and cultures subsequently developed.Native Americans were greatly affected by the European colonization of the Americas, which began in 1492, and their population declined precipitously due to introduced diseases, warfare and slavery.