It’s going to be a long summer for California winemakers. The labor shortage is so acute in Napa and Sonoma counties that grape growers are trucking in workers from miles away and paying them higher wages. But even with these incentives, there may not be enough manpower to pick the grapes once harvest season arrives in August.

However, this isn’t the first time that the California wine industry faced the prospect of their crop dying on the vine.

The discovery of a gold nugget on the American River in 1848 prompted thousands of men to leave their homes and jobs, and rush to California’s gold fields in the foothills of the Sierra Nevada mountains. So many people were panning for treasure in the hopes of making it rich, quick, that there was nobody left to harvest grapes and other crops, even though the demand for food was great.

California, which had been part of Mexico until 1848, tried to solve the labor shortage in the spring of 1850 with a law that essentially enslaved Native Americans so they could be put to work in the vineyards.

Nicknamed the Indian Indenture Act, which was, in fact, the very first legislation that the state passed, cruelly stripped California’s Native Americans of most of their rights. It allowed any white man to identify a Native American as vagrant, lazy, or drunk, which would permit a marshal or sheriff to arrest and fine him. Since most Native Americans could not pay theses fines, a week’s worth of their labor would be auctioned off to the highest bidder, who would then pay the fines. The Native Americans couldn’t protest against their treatment because the law also prohibited them from testifying against white men in court

“Over the next thirteen years, thousands of natives were arrested and sold,” wrote the historian Richard Stevens Street in Beasts of the Field: A Narrative History of California Farmworkers, 1769-1913.

As a result, “Much of the work connected with the grape industry was done by Indians,” wrote Harris Newmark, a Prussian Jew who immigrated to Los Angeles in 1853, in his landmark memoir Sixty Years in Southern California. “Stripped to the skin, and wearing only loin-cloths, they tramped with ceaseless tread from morn until night, pressing from the luscious fruit of the vineyard the juice so soon to ferment into wine.”

Los Angeles, which was the heart of the California wine industry in the 1850s, passed its own, more onerous law to ensure winery owners had the staff they needed to cultivate the vines. Not only could any lawman arrest an inebriated Native American and put him to work in a chain gang, they got a $1 kickback for every eight men they arrested.

One place where many men were rounded up was in the center of the city along a small dead end street known at the time as “Calle De los Negros.” Bars, gambling dens, and brothels lined the block and the collision of money, women, and alcohol made murder a common occurrence. (In 1871, the street was also the site of a horrific riot that killed 17 Chinese-American men.)

Native Americans flocked to the area and on Sundays, the marshal would hook up a wagon and collect the inebriated. He would put them in a corral to sober up and then auction off their labor in the morning.

“Sometimes of a Monday morning we have seen the Marshal marching in a procession with twenty or twenty-five of these poor people; and truly, it is a brave sight,” reported the Los Angeles Star on Dec. 3, 1853.

Theoretically, the Native Americans could have escaped their detention if they could have paid the then exorbitant $2.50 fine, $1 of which was the marshal’s fee. But of the 3,700 Native Americans in Los Angeles at the time, only 334 had the means to get out of jail, Street determined after examining the 1850 census.

“It was impossible for them to buy their freedom,” wrote Street. “Indeed, there is no record of a single man doing so.”

Once the winemakers had purchased their labor for the week, they only had to lead the Native Americans, who were frequently chained together, a short way to the vineyards. There were about 125 vineyards in Los Angeles in the 1850s, so many that the pueblo earned the nickname “The City of Vines.” Many were clustered around the Los Angeles River or in plots around the city. One area, near Aliso Street, became known as “French Town” because so many Frenchmen were cultivating vines around there. At the end of a week, the vineyard owners would often pay the Native Americans in cash or aguardiente, a high-alcohol fortified wine, therefore assuring the cycle of indentured servitude would be repeated.

The financial incentive to grow grapes and make wine was enormous. Growers could make $200 an acre, “much greater than the tillage of the soil for any other kind of fruit or produce,” according to an 1856 article by the California Farmer and Journal of Useful Sciences.

The California Legislature exempted growers from paying any taxes on vines until they were four years old, thus providing more reason to plant. The number of grape vines in California went from about 32,234 in 1855 to 6 million by 1859.

“Nearly every land owner caught the wine fever, entertaining the idea that the planting of a few thousand vines would make him rich and vineyards sprung up, as if by magic, all over California,” wrote Charles Kohler, one of the state’s most successful 19th century winemakers.

While the enslavement of Native Americans helped the industry meet the huge demand for its wine, the practice was not universally embraced. Horace Bell, who had been a Texas Ranger and who ran one of L.A.’s many newspapers, compared the treatment of Native Americans to that of black slaves in the South.

“Los Angeles has a slave mart as well as New Orleans and Constantinople—only the slave at Los Angeles was sold fifty-two times a year as long as he lived, which generally did not exceed one, two, or three years under the new dispensation,” Bell wrote in his book, Reminiscences of a Ranger. “Those thousands of honest, useful people were absolutely destroyed in this way.”

While there were approximately 100,000 Native Americans when California joined the United States in 1850, by 1870 there were about 30,000. And just 219, according to historians, remained in Los Angeles.

Some of the Native Americans moved away but many more died from a combination of factors, including disease (smallpox was particularly brutal), poverty, abuse, and alcoholism. White settlers killed thousands, too, in the so-called Indian Wars. However, the effect of the Indian Indenture Act cannot be underestimated.

“Indeed, California’s systems of Indian servitude… would become a major component of California’s genocide,” wrote Benjamin Madley in An American Genocide: The United States and the California Indian Catastrophe.

On April 27, 1862, in the middle of the Civil War and four months after Abraham Lincoln’s Emancipation Proclamation, the California Legislature repealed the Indian Indenture Act, ending this horrific chapter in the history of the California wine industry. It was, however, too late to save the state’s population of Native Americans.