How did Washington become a state?

Context: Washington, officially the State of Washington and often referred to as Washington state to distinguish it from the USA's capital, Washington, D.C., is a state in the Pacific Northwest region of the Western United States. Named for George Washington—the first U.S. president—the state was formed from the western part of the Washington Territory, which was ceded by the British Empire in 1846, by the Oregon Treaty in the settlement of the Oregon boundary dispute. The state is bordered on the west by the Pacific Ocean, Oregon to the south, Idaho to the east, and the Canadian province of British Columbia to the north. It was admitted to the Union as the 42nd state in 1889. Olympia is the state capital; the state's largest city is Seattle.

Answer: Washington became the 42nd state of the United States of America in 1889. The United States Congress passed an act enabling the territories of Washington, North Dakota, South Dakota, and Montana to seek statehood.