Timeline: History of Humans in Yellowstone

CE = Common Era (replaces AD)

Year Event
Paleoindian Period
Approx. 11,000 years ago A Clovis point from this period was made from obsidian obtained at Obsidian Cliff.
10,000 years ago Folsom people were in the Yellowstone area as early as 10,900 years ago—the date of an obsidian Folsom projectile point found near Pinedale, Wyoming. Sites all over the park yield paleoindian artifacts, particularly concentrated around Yellowstone Lake. Earliest Humans in Yellowstone
9,350 years ago A site on the shore of Yellowstone Lake has been dated to 9,350 years ago. The points had traces of blood from rabbit, dog, deer, and bighorn. People seem to have occupied this site for short, seasonal periods.
Archaic Period (7,000–1,500 years ago)
7,000 years ago Vegetation similar to what we find today begins to appear. Projectile points begin to be notched.
9,000 years ago Beginning 9,000 years ago until 1,000 common era (CE), people leave traces of camps on shores of Yellowstone Lake.
3,000 years ago Oral histories of the Salish place their ancestors in the Yellowstone area.
1,500 years ago Bow and arrow begins to replace atlatl (throwing spear); sheep traps (in the mountains) and bison corrals (on the plains) begin to be used in the Rocky Mountain region.
1400 Oral histories of the Kiowa place their ancestors in the Yellowstone area from this time through the 1700s. More Historic Tribes
1450 Little Ice Age begins.
1600s North American tribes in the southwest begin acquiring horses in the mid to late 1600s. Ancestors of the Crow may have come into Yellowstone during this time.
1700s Lakota Sioux begin exploring the Yellowstone area.
late 1700s Fur traders travel the rivers into the Yellowstone region. Tribes in the Yellowstone area begin using horses.
1804–1806 The Lewis and Clark Expedition passes within 50 miles of Yellowstone.
1807–1808 John Colter explores part of Yellowstone.
1820s Trappers return to Yellowstone area.
1834–1835 Trapper Osborne Russell encounters Sheep Eaters in Lamar Valley.
1840s Trapper era ends.
1850s Little Ice Age ends, climate begins to warm.
1860 First organized expedition attempts but fails to explore the Yellowstone Plateau.
1862 Gold strike northwest of Yellowstone.
1869 Folsom–Cook–Peterson Expedition.
1870 Washburn–Langford–Doane Expedition; Old Faithful Geyser named.
1871 First Hayden Expedition.
1872 Yellowstone National Park Protection Act establishes the first national park.
1877 Nez Perce (Nee-me-poo) flee US Army through Yellowstone.
1883 Northern Pacific Railroad reaches the North Entrance of the park.
1886 The US Army arrives to administer the park. They stay until 1918.
1894 Poacher Ed Howell captured; National Park Protection Act (Lacey Act) passed.
1903 President Theodore Roosevelt dedicates arch at the North Entrance in Gardiner while on vacation.
1906 The Antiquities Act provides for the protection of historic, prehistoric, and scientific features on, and artifacts from, federal lands.
1908 Union Pacific train service begins at West Yellowstone.
1915 Private automobiles are officially admitted to the park.
1916 The National Park Service Organic Act establishes the National Park Service.
1918 US Army turns over park management to the National Park Service.
1929 President Hoover signs first law changing park’s boundary.
1932 President Hoover expands the park again.
1933 Civilian Conservation Corps established, works in Yellowstone through 1941.
1934 The National Park Service Director’s Order prohibits killing predators.
1935 The Historic Sites Act sets a national policy to “preserve for future public use historic sites, buildings, and objects.”
1948 Yellowstone receives one million visitors.
1949 Nineteen snowplane trips carry 49 passengers into the park in winter.
1955 Mission 66 initiated. The first concession-run snowcoach trips carry more than 500 people into the park in winter.
1959 Magnitude 7.5 earthquake strikes on August 17 west of Yellowstone, killing campers in Gallatin National Forest and affecting geysers and hot springs in the park.
1963 The Leopold Report is issued. Modern Management in Yellowstone
1966 The thermophile Thermus aquaticus discovered in a Yellowstone hot spring. Life in Extreme Heat
1970 New bear management plan begins, which includes closing open-pit dumps in park.
1971 Overnight winter lodging opens in park.
1975 Grizzly bear listed as threatened species in the lower 48 states.
1988 Public Law 100-443 protects hydrothermal features in national parks from geothermal development on adjacent federal lands. Summer of Fire: more than 790,000 acres affected by fires in Yellowstone.
1991 Clean Air Act Amendments require air quality monitoring at sites including Yellowstone, a Class I airshed.
1994 Congress enacts a law allowing a percentage of park entrance fees to be kept in the parks.
1995 Wolves are restored to the park.
1996 Federal buyout of gold mine on Yellowstone’s northeast border is authorized.
1998 The National Parks Omnibus Management Act is passed.
2002 National Academy of Sciences confirms effectiveness of Ecological Process Management (aka natural regulation).
2007 Yellowstone’s grizzly bears removed from federal threatened species list; New winter use plan approved for winters beginning in 2008.
2008 Gray wolf delisted and relisted to endangered species list. Judges rule against the new winter use plan.
2009 Grizzly bears returned to threatened species list. Wolves in Wyoming returned to endangered species list; Interim winter use plan approved for winters 2009–2011. Bioprospecting final EIS completed. Science agenda established for Greater Yellowstone Ecosystem.


Last updated: July 11, 2016

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