Tehama is most commonly believed to be derived from the Wintun word for "high water", though there are others definitions that have been proposed such as "low land", "salmon", "mother nature" or "shallow" — any of which would be an accurate description of a location where the river is normally shallow enough to ford, where fishermen are a common sight during the salmon run, and winter floods are a regular occurrence.

A Nomlaki village of Wintun people once stood on the site of modern-day Tehama on the western bank of the Sacramento River.

The four men travelled northward from San Francisco, and were each given land grants from the government of Mexico in 1844, with Thomes' portion being Rancho Saucos.

When the boats started going farther up the river, Red Bluff became the center of trade.

Tehama had a reputation of being somewhat more liberal and freewheeling than the rest of the county, being the last town to go "dry" before Prohibition, and a center for bootleggers and gamblers.

Tehama's population peaked in the 1890s, at about 2000 residents, including a sizable Chinese quarter.

A disastrous fire in 1908 combined with the decline of the riverboat traffic, caused the city to gradually lose prominence and population.

This gives Tehama a distinctive appearance, since by city ordinance, houses must be raised above flood level, so most homes have high foundations and tall stairways to the front door.

The Tehama County Museum,[4] housed in what was once the Masonic Hall, is located at the corner of C and Third Street.

[5] According to the United States Census Bureau, the city has a total area of 0.8 square miles (2.1 km2), all of it land.

Federally, Tehama is in California's 1st congressional district, represented by Republican Doug LaMalfa.