A people's history · Est. 1850
History of Grass Valley.
One town. A Nisenan valley turned gold strike turned Cornish capital turned quiet foothill city. The full story of Grass Valley, California — Boston Ravine, the Empire, the North Star, the Idaho-Maryland, and the people who stayed.
1850
Gold found at Gold Hill
1860
Incorporated as a city
75%
Cornish at peak
1942
Mines shut for WWII
The short version
A gold camp that grew into a Cornish town.
Grass Valley sits on land that was Nisenan country for thousands of years before anyone wrote it down. The town as the maps know it began in October 1850, when miners struck gold at Gold Hill. A camp grew around the strike — first Boston Ravine, then Centerville — and in 1852 it was renamed Grass Valley.
What set Grass Valley apart from a hundred other Gold Rush camps was the geology: most of the gold here was locked in hard rock, not loose in the streams. That meant shafts, stamp mills, and skilled labor — which is why Cornish miners from the UK, already the world's best at deep-shaft tin mining, came over in waves. Between 1860 and 1895 they made up roughly three quarters of the population.
Three mines did most of the work. The Idaho-Maryland led from 1868 to 1900. The Empire and the North Star — both eventually run by the Bourn family — led from 1900 until war shut them down in 1942. The Idaho-Maryland was the second-largest gold producer in the United States by 1938. In 1932 the Empire and North Star were physically connected underground, miles of tunnel knit together beneath the city.
Mining tried to come back after WWII and quietly failed. By the mid-1950s it was over. What stayed was the town itself — the Victorian Main Street, the pasty shops, the Cornish Christmas and St. Piran's Day, and a community shaped by a century of people who came from somewhere far away to work very deep underground.
The timeline
175 years in 17 moments
Pre-1850
Nisenan homeland
The valley and ridges around present-day Grass Valley and Nevada City were the homeland of the Nisenan people for thousands of years before the Gold Rush.
1850
Gold strike at Gold Hill
In October 1850, gold was discovered at Gold Hill. A camp grew up around the strike — first called Boston Ravine, then Centerville. The California Gold Rush had reached the valley.
1851 – 1852
A post office, a name
A post office was established in 1851. The next year, for reasons history never recorded, the town was renamed Grass Valley.
1860
Incorporation
Grass Valley was officially incorporated as a city, anchoring what was already the densest hard-rock gold-mining district in California.
1860s – 1890s
The Cornish arrive
Cornish tin miners from the UK — masters of deep-shaft hard-rock mining — emigrated in waves. By the late 1800s they made up roughly three quarters of the town's population.
1865
After Lincoln
News of President Lincoln's death set off open celebration by some residents. A detachment of 25 men from the 1st Battalion of Native Cavalry, under Second Lieutenant M. E. Jimenez, rode into town, fought a brief skirmish with ten locals, and arrested all ten to Camp Low.
1868 – 1884
Diocese of Grass Valley
Grass Valley briefly held its own Roman Catholic diocese, before the see was relocated to Sacramento — now a titular see.
1868 – 1900
Idaho-Maryland leads
The Idaho-Maryland mine was the most productive in the district. In 1893 Samuel P. Dorsey consolidated the Idaho and Maryland mines into a single operation.
1878
William Bourn Jr. takes Empire
After his father's death, William Bowers Bourn II took over management of the Empire Mine — replacing water power with steam and turning Empire into one of California's richest mines.
1884
Bourn buys North Star
Bourn purchased and rejuvenated the North Star mine. For the next forty years, the Empire and North Star produced more gold than anything else in Nevada County.
1925
MacBoyle's Idaho-Maryland
Errol MacBoyle acquired the Idaho-Maryland. By 1938 it was the second-largest gold producer in the entire United States.
1932
Empire and North Star connect
The two great mines were physically joined underground at the 4,600 and 5,300 foot levels — a single labyrinth running miles beneath the town.
1942
War Production Board Order 208
Gold mining was shut down across the country to free labor and equipment for the WWII war effort. Grass Valley's mines went dark.
Mid-1950s
The end of mining
Operations were attempted again after the war, but as historian Gage McKinney put it: 'by the mid-1950s mining was no longer profitable in what had been the richest gold mining district in California.' The Bourn and Starr families later donated mine property that became Memorial Park.
1981 – 2021
The last California Kmart
Grass Valley's Kmart, opened in 1981, ended up the last surviving Kmart in California when it closed in 2021. A Target now stands on the same lot.
Today
Cornish heritage, live
Grass Valley still leans hard into its Cornish roots — annual Cornish Christmas on Mill Street, St. Piran's Day in March, pasty shops handing down original immigrant recipes, and a sister-city bond with Bodmin, Cornwall.
The Cornish chapter
Why Grass Valley still eats pasties.
When the Cornish tin industry collapsed in the mid-19th century, thousands of experienced hard-rock miners looked for work overseas. Grass Valley — with its deep quartz veins — was the perfect destination.
They brought the pasty, a self-contained meat-and-vegetable hand pie originally designed to be eaten one-handed at the bottom of a mine shaft. Several shops in town still serve recipes handed down from those first immigrant generations.
They brought Cornish Christmas, now a multi-Friday street fair on Mill Street every December, and St. Piran's Day in March, marking the Cornish patron saint.
And they made Grass Valley a sister city to Bodmin, Cornwall — a quiet civic acknowledgement of where so many local family trees actually start.
The story is still being written.
grassvalley.app is the open community network for Grass Valley & Nevada City — events, neighbors, and what's happening on Mill Street tonight.
Historical facts adapted from public sources including Wikipedia (CC BY-SA 4.0).