Historical Maps

 Humboldt and Trinity Counties

Counties are political creations. As such, their boundaries have often shifted with the winds of political change. As the states grew in population and sought to maintain political balance over time, new counties were created or eliminated. Often counties were merged or split. So it was in California. In the first five years of California's statehood, county boundaries were changed five times!

These changes are important for genealogy. As you search for your family's roots, you will need to know where to search for information. For example, if family tradition says that your ggg grandfather was born in Trinity County, California in 1850, it is important for you to know that Trinity County in 1850 was composed of Del Norte and Humboldt counties, and parts of Siskiyou and Shasta counties in addition to all of what is now Trinity County. Humboldt County wasn't even created until 1853.

The maps on this page show the changes in the boundaries of Trinity and Humboldt counties in 1850, 1851, 1852, 1853, 1855, and 1875. The northern edge of each map is the Oregon-California border, and the eastern edge is the Nevada-California border. Neighboring counties are labeled for reference. Each map is accompanied by descriptive text.

The county outline maps are provided courtesy of Gold Bug Historic Maps & Software at http://www.goldbug.com

1850 1851 1852 1853 1855 1875




California entered statehood with 27 original counties. Trinity County was one of these. Its borders stretched from the 40th parallel on the south, the Pacific Ocean on the west, the Oregon border on the north, and just west of Lower Klamath Lake following a jagged line to the Sacramento River on the east.

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With the 1851 boundary adjustments, Klamath, a new county, was created by dividing Trinity County at the 41st parallel.

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In the 1852 adjustment of county boundaries, Siskiyou County took a large portion of Klamath County east of the Klamath Mountains.

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The 1853 county adjustment saw the creation of Humboldt County out of land that had formerlly been Trinity County. Trinity County was divided at 123� 30'.

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The adjustment of 1855 gave Trinity County the southeast corner of Klamath County.

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A final adjustment in 1875 eliminated Klamath County, created Del Norte County, with Crescent City as the county seat, and apportioned the rest of Klamath County to Humboldt and Siskiyou counties.

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For a colorful view of Trinity County in 1890... click for a larger view.

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