"You don't look like you're from around here," a young Adolphus Busch is told as he arrives in America from Germany to pursue his dream of making beer. So begins Budweiser's new Super Bowl ad, released earlier this week into an ongoing political maelstrom over immigration.

The ad depicts the company's founder trudging through swamps and mud, surviving a steamboat fire and being greeted with outright hostility before getting to St. Louis and meeting Eberhard Anheuser — i.e., the Anheuser in Anheuser-Busch. Despite the beer giant's protestations that the ad is not political, it has hit a nerve among conservatives for taking a seemingly pro-immigrant stance at a time of widespread protests against President Trump's ban on travelers from seven Muslim-majority nations.

But lost in all the brouhaha is the true story of the 19th century German immigrants behind the rise of American brewing.

First, let's start with a little historical nitpicking with that ad. Historian Maureen Ogle, author of Ambitious Brew: The Story of American Beer, says that when Busch arrived in St. Louis, he didn't just run into Eberhard Anheuser — he married his daughter and took over the small brewery that Anheuser, a prosperous soap-maker, had acquired.

Also, neither Anheuser nor Busch was the source of the original Budweiser. Ogle says the Bud brand was started by one of Busch's friends, Carl Conrad. Busch eventually bought Budweiser from Conrad — but that happened in the 1880s, long after he had already become a successful brewer.

But there's one thing in the Budweiser ad that rings true to history: the anti-German immigrant hostility that Busch is depicted enduring on the streets. "Go back home!" a man tells him angrily.

While we don't know whether Busch himself ever walked through such hostile crowds, Ogle says the 1850s were certainly an era marked by "xenophobic turmoil."

Busch was part of a large wave of German immigrants, including Frederick Miller and Frederick Pabst, who helped build American brewing in the mid-1800s. The still-new nation was in the middle of a great debate over what it meant to be an American. And it was seeing a huge influx of immigrants — not just from Germany, but Ireland, too.

"Both the Irish and Germans came from cultures where alcohol was a respectable habit," says Ogle.

Many native-born Americans were worried about how all those newcomers, and their customs, would affect national identity, Ogle says. That's partly what gave rise to the temperance movement. It wasn't just about condemning alcohol, it was about defining the moral character of America.

"That was a serious culture clash," Ogle says. "And it did fuel a really strong Prohibition movement."

Many Germans who came over set up beer halls in towns with large German enclaves, like St. Louis, Cincinnati and Milwaukee.

"Americans thought of it as disreputable — only low-class people drank," Ogle says. "If you went into a tavern, you were going into the seventh circle of hell."

This was the 1840s and '50s, when America was still debating the great question of slavery, and whether to legalize it outside the South. Ogle says many working-class whites in the North who organized against the expansion of slavery did so, in part, out of fear that they'd be competing for low-skill jobs. These working-class whites were anti-immigrant for the same reasons, she says.

"There were pitched battles in the streets where people were saying, 'You don't belong here. Go home. We don't want any more immigrants, ' " Ogle says.

The Republican Party was born in Wisconsin in this climate, she says, to combat the expansion of slavery into the Western territories, but also as a way for German immigrants to stand up for themselves.

"In Milwaukee [the Republican Party] was made up of German immigrants who were determined to protect immigrant rights and who wanted to end slavery," she says.

As for Busch, he became an American citizen and was extremely proud of it, Ogle says. He died before the start of World War I — when anti-German sentiment became rampant in the U.S. His wife, Lilly Anheuser Busch, suffered a terrible indignity. Suspected of being a German spy, she was forced to undergo a full-body exam — body cavities included — by order of the attorney general on her way back from visiting relatives in Germany. And his family was denounced in newspapers as un-American, their loyalties to the nation openly questioned.

One other thing to note: Many of those German immigrants of the mid-19th century were essentially refugees. They were fleeing constant warfare in Europe and came to America in search of stability.

So while Budweiser's ad represents a glowing representation of the American dream, the truth is more complicated and, in fact, reflects a history of immigration that reverberates today.

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