18,000 B.C. Earliest evidence of humans in Wyoming.

11,000 B.C. Earliest evidence of humans in Montana.

A.D. 1620s Arrival of the Plains Indians.

A.D. 1807 John Colter explores the Yellowstone area, going as far south as Jackson Hole.

1867 The Union Pacific Railroad enters Wyoming.

1876 Warriors from the Sioux, Lakota, and Cheyenne tribes defeat General George A. Custer and his troops at the Battle of the Little Bighorn. (Montana)

1883 The Northern Pacific Railroad crosses Montana.

1889 Montana, on November 8, becomes the 41st state in the Union.

1890 Wyoming becomes the nation's 44th state.

1929 Grand Teton National Park is established, consisting of only the main peaks of the Cathedral Range.

1950 National forest and private lands are added to Grand Teton National Park, forming the park's current boundaries.

2008 The gray wolf population in the Northern Rockies hits 1,600; the species is no longer listed as endangered.

2009 Montana has its first legal wolf-hunting season since reintroduction in 1995.

2010 A court ruling returns the grizzly bear to the threatened species list.

2010 A court ruling returns the gray wolf to the endangered species list.

2011 The U.S. Congress returns gray wolf management to the states, effectively delisting the species again in Wyoming and Montana.

2016 The Interagency Grizzly Bear Committee recommends that the grizzly bear be taken off the Endangered Species List.

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