Presented with permission, as excerpted from the WSHM Field Guide to the Hall of Washington History, a publication of the Washington State Historical Society. Please visit their website.

40-17 million years ago
The Cascade Mountains are formed. The Olympic Mountains appear as islands in the Pacific.

17-6 million years ago
Floods of lava cover the Columbia Basin and destroy the Columbia River waterway.

6 million - 10,000 years ago
Washington's Ice Age. Volcanos form in the Cascades and huge glaciers cover the mountains and Puget Sound. Floods shape the southern part of the state.

11,000 B.P.
People of the Clovis Culture inhabit the Northwest

6,700 B.P.
Mount Mazama erupts

1741-43
Russian explorers reach Alaskan islands and coast and trade with native peoples for sea otter pelts.

1774
Juan Perez commands the first Spanish expedition to explore the Northwest Coast and sights the Olympic Mountains

1775
Bruno de Hezeta lands on the Washington coast and claims the area for Spain. On his return south, he sees the mouth of the Columbia River.

1778
James Cook (British) explores and charts the Northwest Coast.

1789
George Washington is elected the first president of the United States.

1792
Robert Gray (American) names the Columbia River after his ship.

George Vancouver (British) explores and names Puget Sound and Lieutenant William Broughton explores the Columbia River up to Point Vancouver.

Spain establishes the first non-Indian settlement in Washington at Neah Bay. 1805-06
Lewis and Clark enter Washington and stay at Fort Clatsop on the south side of the mouth of the Columbia River

1807-11
David Thompson charts the Columbia River

1825
Hudson's Bay Company establishes forts Vancouver and Colvile on the Columbia

1841
United States naval expedition, headed by Charles Wilkes, explores Washington

1843
First large immigration to Oregon occurs and temporary government established

1846
Treaty between United States and Great Britain sets boundary at 49th parallel

1847
Cayuse Indians attack Whitman Mission in Walla Walla

1848
Oregon Territory created

1851
First settlers land on the site of Seattle

1853
Washington Territory created

1855-58
Yakima Indian War

1855
Walla Walla Treaty Council

1860s
Gold and silver discovered in the Okanogan

1883
Northern Pacific Railroad completed to Tacoma, linking Washington to the East

1886
Coal mining town of Roslyn founded; Mine operated by the Northern Pacific Coal Company

1888
Stampede Tunnel of the Northern Pacific Railroad completed across the Cascades

1889
Washington becomes the 42nd state

1893
Great Northern Railroad completed to Seattle

1897-99
Klondike Gold Rush; Seattle grows quickly as a jump-off point for people heading to the gold fields

1899
Mount Rainier National Park established

1900
Frederick Weyerhaeuser sets up a logging business in western Washington

1902
Reclamation Service begins irrigation project in Yakima and Okanogan valleys to facilitate farming

1903
Iron Chink fish cleaning machine invented by Seattleite Edmund A. Smith

1909
Alaska-Yukon-Pacific Exposition held in Seattle to showcase the Northwest's setting and bounty of natural resources
Mount Olympus National Monument established

1910
Women gain the right to vote in Washington

1914
Finnish immigrant Oscar Wirkkala invents the "spar logging" technique

1914-1918
World War I

1917
Spruce Army originated
Fort Lewis (United States Army) established

1919
Seattle general strike; labor violence in Centralia

1929
U.S. stock market crashes 1931
Hoovervilles appear in many cities, glaring evidence of high unemployment rates

1933
President Franklin D. Roosevelt begins New Deal programs; Grand Coulee Dam begun

1937
Bonneville Dam on the Columbia River completed

1941
Grand Coulee Dam completed
United States enters World War II
December: Pearl Harbor, Hawaii bombed by Japan

1943
Hanford Engineer Works built to produce plutonium for the WWI bomb "Little Boy"

1939-45
World War II August: U.S. bombs Hiroshima and Nagasaki to help end WWII 1948
Washington's first TV station (KING-TV) begins broadcasting in Seattle

1954
First flight of Boeing 707, first jet transport

1957
Washington Public Power Supply System (WPSS) created to develop Washington's energy resources

1962
Seattle World's Fair

1975
Microsoft founded, major producer of computer software

1976
Dixy Lee Ray, first woman governor of Washington elected

1980
Mount St. Helens erupted, scattering ash throughout the state

1987
Clovis Points discovered in an East Wenatchee orchard

1989
Washington's centennial of statehood

1996
The new Washington State History Museum opened