The West Coast of the United States, also known as the Pacific Coast and the Western Seaboard, is the coastline along which the Western United States meets the North Pacific Ocean. The term typically refers to the contiguous U.S. states of California, Oregon, and Washington, but it occasionally includes Alaska and Hawaii in bureaucratic usage. For example, the U.S. Census Bureau considers both states to be part of a larger U.S. geographic division.
Definition There are conflicting definitions of which states comprise the West Coast of the United States, but the West Coast always includes California, Oregon, and Washington as part of that definition. Under most circumstances, however, the term encompasses the three contiguous states and Alaska, as they are all located in North America. For census purposes, Hawaii is part of the West Coast, along with the other four states. Encyclopædia Britannica refers to the North American region as part of the Pacific Coast, including Alaska and British Columbia. Although the encyclopedia acknowledges the inclusion of Hawaii in some capacity as part of the region, the editors wrote that "it has little in common geologically with the mainland states."
Several dictionaries offer different definitions of the West Coast. Lexico restricts the West Coast's definition to "the western seaboard of the U.S. from Washington to California." However, Macmillan Dictionary provides a less specific definition as "the western coast of the U.S., along the Pacific Ocean." As for the Cambridge Dictionary, the West Coast is "the area of the Pacific coast in the U.S. that includes California."
History
The history of the West Coast begins with the arrival of the earliest known humans of the Americas, Paleo-Indians, crossing the Bering Strait from Eurasia into North America over a land bridge, Beringia, that existed between 45,000 BCE and 12,000 BCE (47,000–14,000 years ago). Small isolated groups of hunter-gatherers migrated alongside herds of large herbivores far into Alaska. Between 16,500 BCE and 13,500 BCE (18,500–15,500 years ago), ice-free corridors developed along the Pacific coast and valleys of North America and possibly by sea.
Alaska Natives, Indigenous peoples of the Pacific Northwest Coast, and California indigenous peoples eventually descended from the Paleo-Indians. They developed various languages and established trade routes.
Later, Spanish, British, French, Russian, and American explorers and settlers began colonizing the area.
The West Coast was officially incorporated into the United States in 1848, through the establishment of the Oregon Territory; and in 1850, through the admission of California to the Union.
The Oregon Territory was previously jointly administered by the United States and the United Kingdom as part of the Oregon Country, and its boundary was established by the Oregon Treaty in 1846. In 1853, the Washington Territory was split from the Oregon Territory, and these territories were admitted as the West Coast states of Oregon, in 1859; and Washington, in 1889.Horner, John B. (1919). Oregon: Her History, Her Great Men, Her Literature. The J.K. Gill Co.: Portland. pp. 28–29.
The area of the state of California, in turn, was ceded to the United States by Mexico in the Treaty of Guadalupe Hidalgo, in 1848, after the Mexican–American War. California was later admitted as the 31st state in 1850 as a free state.
On May 10, 1869, the first transcontinental railroad was completed joining the West Coast to the East of the United States.
Climate
The West Coast of the United States has an oceanic climate in its Northwestern, Northern, and Eastern edge towards the U.S.-Canada border, but from Northern California, towards the U.S.-Mexico border the climate is Mediterranean. While the northern half of the west coast, particularly coastal Washington and Oregon has moderate rainfall, particularly during the winter months, much of coastal California is drier year-round.
The coastline sees significantly milder temperatures compared to inland areas during summer. In far Northern California there is a difference of 17 °C (30 °F) between Eureka and Willow Creek despite only 25 miles (40 km) separating the locations and Willow Creek being located at a elevation. Slightly narrower fluctuations can be seen all through the coastline, and could partially be explained by the cold currents in the Pacific Ocean moderating coastal temperatures and the mountain ranges blocking the maritime air from moving farther inland than its foothills during summer.
Coastal fog is also prevalent in keeping shoreline temperatures cool. While famous in the San Francisco Bay Area, coastal fog also affects Santa Monica in Los Angeles, Southern California, leading to May gray and June gloom conditions. Coastal California has very little yearly temperature differences with cool summers similar to those expected in parts of Northern Europe in San Francisco but warmer temperatures year-round further south. A short journey inland and summer temperatures are comparable with the rest of the United States on the same latitudes, sometimes warmer due to prevailing winds from the Nevada and Arizona hot desert climate.
Government and politics With the exception of Alaska, the Democratic Party has dominated West Coast politics in contemporary history, with the states consistently voting for Democrats in elections at various levels. Four out of five West Coast states have voted for Democrats in presidential elections since 1992, three of which have done so since 1988.
State governments +Governors of the West Coast State GovernorParty Term Start End Republican2026 Democratic2027 Democratic2026 Democratic2027 Democratic2029
Ideology and party strength
In politics, the West Coast usually refers to the contiguous coastal states of California, Oregon, and Washington because of their similar political leanings. In 2017, The Oregonian columnist David Sarasohn described the West Coast as a "blue wall" of shared values on immigration, abortion, climate change, and civil liberties. By 2016, the West Coast states legalized marijuana after California voted to do so. According to a 2019 Pew Research Center poll, 72% of adults in Pacific states said that "climate change is affecting their local community at least some", higher than in any other region in the country.
Since 1992, the three states have voted for Democrats in presidential elections without interruption, but Oregon and Washington also voted for the Democratic presidential candidate in 1988.
In the 2010s, Democrats strengthened their political power along the West Coast. After winning a special election for a seat in the Washington state senate in 2017, Democrats built a government trifecta in all three West Coast states. For the 2022 U.S. House of Representatives elections, Democrats controlled all congressional districts touching the Pacific until 2024 when Alaska flipped Republican. Hawaii is not usually considered part of the West Coast in the political definition, though it is considered a Democratic stronghold. Before achieving statehood in 1959, Hawaii became a state favorable to Democrats to the point that they sought statehood for the territory. Southern Democrats opposed the move because it would mean additional votes against their region on several issues. Since achieving statehood, Hawaii consistently voted for Democrats in presidential elections, except in 1972 and 1984.
Unlike the other West Coast states, Alaska has been a reliable state for Republicans in presidential elections. Since achieving statehood, Alaska has voted for the Democratic presidential candidate only once in 1964. In 1960, the state narrowly voted for Republican Richard Nixon over Democrat John F. Kennedy and had voted for Republicans uninterrupted since 1968. All five West Coast states united in voting for Johnson in his 1964 landslide, while in 1972 and 1984, this occurred again as Nixon and Reagan got support from all 5.
Presidential election history Parties Democratic Republican Progressive Bold denotes election winner + Presidential electoral votes in the Pacific States since 1852Year Alaska California Hawaii Oregon Washington 1852 No election Pierce No election No election No election 1856 No election Buchanan No election No election No election 1860 No election Lincoln No election Lincoln No election 1864 No election Lincoln No election Lincoln No election 1868 No election Grant No election Seymour No election 1872 No election Grant No election Grant No election 1876 No election Hayes No election Hayes No election 1880 No election Hancock No election Garfield No election 1884 No election Blaine No election Blaine No election 1888 No election Harrison No election Harrison No election 1892 No election Cleveland No election Harrison Harrison 1896 No election McKinley No election McKinley Bryan 1900 No election McKinley No election McKinley McKinley 1904 No election Roosevelt No election Roosevelt Roosevelt 1908 No election Taft No election Taft Taft 1912 No election Roosevelt No election Wilson Roosevelt 1916 No election Wilson No election Hughes Wilson 1920 No election Harding No election Harding Harding 1924 No election Coolidge No election Coolidge Coolidge 1928 No election Hoover No election Hoover Hoover 1932 No election Roosevelt No election Roosevelt Roosevelt 1936 No election Roosevelt No election Roosevelt Roosevelt 1940 No election Roosevelt No election Roosevelt Roosevelt 1944 No election Roosevelt No election Roosevelt Roosevelt 1948 No election Truman No election Dewey Truman 1952 No election Eisenhower No election Eisenhower Eisenhower 1956 No election Eisenhower No election Eisenhower Eisenhower 1960 Nixon Nixon Kennedy Nixon Nixon 1964 Johnson Johnson Johnson Johnson Johnson 1968 Nixon Nixon Humphrey Nixon Humphrey 1972 Nixon Nixon Nixon Nixon Nixon 1976 Ford Ford Carter Ford Ford 1980 Reagan Reagan Carter Reagan Reagan 1984 Reagan Reagan Reagan Reagan Reagan 1988 Bush Bush Dukakis Dukakis Dukakis 1992 Bush Clinton Clinton Clinton Clinton 1996 Dole Clinton Clinton Clinton Clinton 2000 Bush Gore Gore Gore Gore 2004 Bush Kerry Kerry Kerry Kerry 2008 McCain Obama Obama Obama Obama 2012 Romney Obama Obama Obama Obama 2016 Trump Clinton Clinton Clinton Clinton 2020 Trump Biden Biden Biden Biden 2024 Trump Harris Harris Harris HarrisYear Alaska California Hawaii Oregon Washington
Demographics
According to the results of the 2020 U.S. census, 16 of the 20 largest cities on the West Coast are in California. The cities of Los Angeles, San Diego, and San Jose are all among the ten most populous in the U.S. and each has more than a million residents. Los Angeles is nearly three times more populous than San Diego. Behind these three cities, San Francisco, Seattle and Portland are respectively fourth, fifth, and sixth in population for West Coast cities. Hawaii's capital and largest city, Honolulu, is the 13th largest city, and Alaska's largest city, Anchorage, is 17th on the West Coast. +Top 10 largest cities on the West Coast City Population (2020) Los Angeles 3,898,747 San Diego 1,386,932 San Jose 1,013,240 San Francisco 873,965 Seattle 737,015 Portland 652,503 Fresno 542,107 Sacramento 524,943 Long Beach 466,742 Oakland 440,646 Source: U.S. Census Bureau; U.S. Department of Energy
Culture California's history first as a major Spanish colony, and later as Mexican territory, has given the lower West Coast a distinctive Hispanic-American tone, which it also shares with the rest of the Southwest. Similarly, two of the three cities in which Asian Americans have concentrated, San Francisco and Los Angeles, are located on the West Coast, with significant populations in other West Coast cities. San Francisco's Chinatown, the oldest in North America, is a noted cultural center.