Colusa is a city and county seat of Colusa County, California, located in the Sacramento Valley region of the Central Valley. The population was 5,971 at the 2010 census, up from 5,402 at the 2000 census. Colusi originates from the local Coru Native American tribe, who in the 1840s lived upon the opposite side of the Sacramento River.

In 1850, Charles D. Semple purchased the Rancho Colus Mexican estate grant on which Colusa was founded and called the place Salmon Bend. The town was founded, under the herald Colusi, by Semple in 1850. The first post office was conventional the behind year, 1851. The California legislature tainted the town’s (and the county’s) name to Colusa in 1854. The town flourished due to its location upon the Southern Pacific Railroad. Several travelers flaming stops were established at various road distances from Colusa, including Five Mile House, Seven Mile House, Nine Mile House, Ten Mile House, Eleven Mile House, Fourteen Mile House (also called Sterling Ranch), Sixteen Mile House (at the current location of Princeton), and Seventeen Mile House. The native settlement of what became Colusa was originally placed at the site of Seven Mile House but taking into account removed to its current site in 1850.

On July 10, 1887, convicted murderer Hong Di, an immigrant from China, was dragged from the Colusa jail and was goaded by exceeding a hundred and fifty men through the streets of Colusa’s Chinatown, before he was hanged from the rafters of the locomotive turntable of the Colusa and Lake Railroad. Di, who had worked as a servant for the Billiou intimates of St. Johns, California, had shot and killed his employer Julie Billiou on April 7, 1887. He was captured upon May 22, 1887, near Gridley, California.

According to the United States Census Bureau, the city has a total area of 1.8 square miles (4.7 km), all of it land. According to the United States Geological Survey, the city’s location is at 39°12′52″N 122°00′34″W / 39.21444°N 122.00944°W / 39.21444; -122.00944.