Washington Historical Geography

Oregon Territory
Originally inhabited by Native Americans, the region that became the Oregon Territory was explored by Europeans first by sea. The first documented voyage of exploration was made in 1777 by the Spanish, and both British and American vessels visited the region not long thereafter. Subsequent land-based exploration by Alexander Mackenzie and the Lewis and Clark Expedition and development of the fur trade in the region strengthened the competing claims of Great Britain and the United States.

The competing interests of the two foremost claimants were addressed in the Treaty of 1818, which sanctioned a "joint occupation", by British and Americans, of a vast "Oregon Country" (as the American side called it) that comprised the present-day U.S. states of Oregon, Washington, and Idaho, parts of Montana and Wyoming, and the portion of what is now the Canadian province of British Columbia south of the parallel 54°40′ north.

Washington Territory and Statehood
The growing populace of Oregon Territory north of the Columbia River formally requested a new territory. As a result of the Monticello Convention, held in present-day Cowlitz County, Congress passed legislation and President Millard Fillmore signed into law on March 2, 1853, the creation of a new Washington Territory. The boundary of Washington Territory initially extended farther east than the present state's, including what is now the Idaho Panhandle and parts of western Montana, and picked up more land to the southeast that was left behind when Oregon was admitted as a state. The creation of Idaho Territory in 1863 established the final eastern border. Although never approved by Congress, the 1878 constitution is an important historical document which shows the political thinking of the time. It was used extensively during the drafting of Washington State's 1889 constitution, the one and only official Constitution of the State of Washington. Washington became the 42nd state in the United States on November 11, 1889.

Early prominent industries in the state included agriculture and lumber. In eastern Washington, the Yakima River Valley became known for its apple orchards, while the growth of wheat using dry farming techniques became particularly productive. Heavy rainfall to the west of the Cascade Range produced dense forests, and the ports along Puget Sound prospered from the manufacturing and shipping of lumber products, particularly the Douglas fir. Other industries that developed in the state included fishing, salmon canning and mining.

Early Counties

 * The Provisional Government of Oregon established Vancouver and Lewis Counties in 1845 in unorganized Oregon Country, extending from the Columbia River north to 54°40′ North latitude.
 * After the region was organized within the Oregon Territory with the current northern border of 49°N, Vancouver County was renamed Clarke, and six more counties were created out of Lewis County before the organization of Washington Territory in 1853.
 * 28 counties were formed during Washington's territorial period, two of which only existed briefly.
 * The final five were established in the 22 years after Washington was admitted to the Union as the 42nd state in 1889.
 * No changes to counties have been made since the formation of Pend Oreille County in 1911, except when the small area of Cliffdell was moved from Kittitas to Yakima County in 1970.

County Boundary Changes

 * Wikipedia Chart of Counties, Creation Dates, and Former Counties Before Creation