On this day in 1933, the Twenty-first Amendment to the United States Constitution was passed, repealing Prohibition. People around the country celebrated Repeal Day, up to and including president Franklin Delano Roosevelt, who received a case of Budweiser carried by the company’s famous draft horses. But one group had little reason to celebrate: the Ku Klux Klan, which had allied itself with Prohibition campaigners intent on “purifying” the country–and prospered as a result.

Speaking to Slate’s Rebecca Onion, historian Lisa McGirr said that the resurgence of the Ku Klux Klan in the 1920s was related to the passage of the Volstead Act, which imposed Prohibition, in 1920. When she looked at how the hate group gathered members, she said, “it was often around the issue of the lack of observance of Prohibition, the issue of bootlegging, of cleaning up communities.” However, these concerns masked other ones, she explained. “This issue was used instrumentally as a mandate to target those groups they already saw as enemies of white Protestant nationalism: immigrants, Catholics and African Americans.”

The Ku Klux Klan’s support of Prohibition gave the organization a way to promote its views and a way to perpetrate state-sanctioned violence against people of color, Catholics and Jews. “The war on alcohol united Progressives and Protestants, federal agents and Klansmen,” writes Kelefa Sanneh for The New Yorker.

The American government created an entire Prohibition Bureau intended to enforce alcohol-free living. However, this bureau selectively targeted groups that were perceived as inherently corrupt, like poor people, immigrants, and African Americans. Remember, the Jazz Age unfolded during Prohibition–plenty of people were drinking plenty of liquor.

The collaboration didn't end there. The underresourced Prohibition Bureau’s agents “sometimes increased their ranks by deputizing volunteers, including members of the Ku Klux Klan, who found the battle to enforce Prohibition consistent with their broader mission to purify the nation,” writes Sanneh. “In 1923, in Williamson County, Illinois, hundreds of enforcers, many of them Klansmen, began a series of violent raids on distilleries, bars, and private homes, in which several hundred people were arrested and more than a dozen were killed.”

In the end, Prohibition didn’t “purify” the nation by stopping drinking. What it did do was foster a nationwide climate of turmoil, and this was great for organizations that benefited from people’s fears and anxieties–like the Klan. McGirr argues that the politics of Prohibition paved the way for today’s far-right nationalist movements–just one example of its long reach.