Welcome to Jefferson County!

All data, photos, and images have been contributed by researchers like yourself and posted by the county coordinator. Contributions are greatly appreciated.

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About Jefferson County

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Jefferson County was named for President Thomas Jefferson and formed out of Thurston County on December 22, 1852, while part of the Oregon Territory. It began with 4,854 square miles of the northern part of the Olympic Penninsula, but 2,670 northwestern square miles were split off to form Clallam County on April 26, 1854. Jefferson County is surrounded by the counties of Clallam, Grays Harbor, Island, Kitsap, and Mason.


On April 24, 1851, the first American settlement was established in Port Townsend. Per the US Census, in 1860, the county had 531 residents, and the population in 2010 was 29,872.

The county is connected to other Washington locations by the Hood Canal Bridge and the Coupeville-Port Townsend ferry.

The county seat and largest town is Port Townsend, and the largest private employer is the Port Townsend Paper Mill. The largest overall employer is Jefferson Healthcare.

Towns and communities in Jefferson County include Adelma Beach, Beaver Valley, Brinnon, Center, Clearwater, Dabob, East Quilcene, Gardiner, Glen Cove, Kalaloch, Mats Mats, Marrowstone, Port Hadlock-Irondale, Port Ludlow, Port Townsend, Queets, Quilcene, and Tukey.

About Us

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Washington GenWeb is part of the USGenWeb Project. The Project is managed by a team of volunteers with the goal of providing free access to genealogical and historical information pertaining to all counties in every state of the USA.

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Jefferson County GenWeb is part of the WAGenWeb Project. To access information for the other counties in Washington State, please see the WAGenWeb page.