The land on which Everett was founded was surrendered to the United States by its original inhabitants under the 1855 Treaty of Point Elliott. Permanent settlement in the area by European descendants started in 1861 when Dennis Brigham built a cabin on a 160-acre claim on the shore of Port Gardner Bay. Over the next several years a handful of settlers moved to the area, but it wasn't until 1890 that plans for platting a town were conceived.

Snohomish was founded around 1858 by Emory C. Ferguson, E. F. Cady and others. It was originally known as Cadyville, but changed its name to Snohomish City in 1871. The name Snohomish comes from the name of the dominant local Native American tribe, whose meaning is widely disputed. One of the first inland cities in the Puget Sound region, Snohomish was built where a planned military road connecting Fort Steilacoom and Fort Bellingham was set to cross the Snohomish River.

Monroe was once the site of the Great Northern Railway's botanical gardens where fresh flowers for their passenger trains were once grown. Each day these flowers would be loaded aboard the Western Star for distribution throughout the system so that each dining car passenger might have fresh flowers with their meal.
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Index -- Thumbnail History HistoryLink.org Essay 9143 :

The area now called Ballard was settled by the Duwamish Tribe after the last glacial period. There were plentiful salmon and clams in the region. The U.S. government code in the CDC  for this group is American Indian, Puget Sound Salish . The Burke Museum has artifacts from the group of Duwamish who lived at Shilshole. The references say that before non-Natives arrived, the group living around Shilshole may have been in decline due to a "great catastrophe".

Seattle's location, harbor, and commercial development made it a logical place for the Great Northern's terminus, and Hill had the good sense to engage the persuasive and influential Thomas Burke as his local agent. Having previously achieved the creation of Railroad Avenue, Burke had little difficulty persuading the city council -- over the vociferous objections of the Northern Pacific -- to give the Great Northern a 60-foot right-of-way down the middle of the wood-planked roadway.