German American voters helped pave Donald Trump's path to the presidency in 2016, drawn to his candidacy by appeals that researchers said resonated with the group's unique historical experience and could impact elections for years to come.

An article published Feb. 26 in Electoral Studies found evidence that German Americans backed Trump both because of ties to the Republican Party but also because of isolationist policy preferences they felt Trump would champion.

Drawing together data on voting returns, census information and the ethnic group's historical background, the study shows how German Americans have a distinct impact on U.S. electoral politics to this day — a finding the authors said challenges widely held assumptions about Trump's appeal and its roots among America's largest self-identified ancestry group.

"The upshot is that until this day, there is a shared political outlook in German American communities consisting of conservatism and a remaining non-partisan isolationist appeal," they wrote, adding that the group's unique attitudes were "particularly relevant" for explaining why key states that had backed former President Barack Obama in 2012 broke for Trump in 2016.

Authors Klara Dentler, Thomas Gschwend and David Hünlich first became interested in the topic when analyses from German media suggested that Americans of German ancestry — particularly in crucial Midwest swing states — might put Trump over the top in the 2016 presidential contest.

"Given the regional concentration of German Americans, the assumptions of the German media did not seem implausible to us," Hünlich told The Academic Times. "But the motivations behind a 'German vote' were unclear because there is no visible 'German American' group."

Many commentators later credited a "white backlash" for Trump's victory, suggesting that white Americans whose ethnic backgrounds had largely faded through time coalesced around their perceived racial affinity, voting in reaction against an increasingly diverse society.

While racism featured prominently in Trump's coalition, the researchers wrote, their findings challenge the "white backlash" hypothesis by uncovering different motives driving many of the country's 46 million German Americans to back the political outsider.

"Two distinct pathways, a partisan and a non-partisan pathway, appear to have driven German Americans towards Trump: a historically grown association with the Republican Party on the one hand, and an acquired taste for isolationist attitudes that can be activated by respective candidates' campaign agendas on the other," they wrote.

Gschwend told The Academic Times he was surprised to find systematic evidence of a cohesive, distinct German American vote at this point in America's history.

"You would not expect that ancestry matters politically in the U.S.," he said. "The more we thought about how this could matter and the better evidence we were able to uncover, the more I changed my initial opinion on that."

The researchers first analyzed county-level voting returns to explore the nature of German Americans' Trump support in 2016. For every 1 percentage-point increase in the share of German ancestry in a county, Trump's advantage over Clinton rose about 2 percentage points, the researchers found.

That "Trump effect" wasn't simply the result of German Americans' preferences for the Republican Party writ large, they discovered. Statistical regressions revealed that counties with a 1 percentage-point increase in the share of German ancestry saw the Republican vote share advantage increase on average by 0.24 percentage points between Republican Mitt Romney in 2012 and Trump's 2016 ticket.

That increase in vote share differential from 2012 to 2016 was larger than it had been between 2008 and 2012, again suggesting that Trump and his unique policy agenda was what drove German Americans to his ticket, rather than a broader realignment in favor of Republicans generically.

"Any other non-isolationist Republican candidate would have been less successful with the German American community," the researchers wrote.

Support from the ancestry group was key to Trump's success, they found. The higher the share of German ancestry in a given county, the more likely that county was to be in a state that swung from the Democratic Party in 2012 to the Republican Party in 2016, holding other factors constant.

While other white ethnic groups, including Irish and "unhypenated" Americans — who don't report a specific European ancestry but simply call themselves "American" — also broke for Trump on balance, they appeared not to have impacted Trump's sometimes razor-thin margins in important states, according to the researchers.

Italian Americans were found to oppose Trump on the whole, according to the study, providing further evidence that support for his campaign wasn't simply a function of a unified "pan-ethnic coalition of white voters."

The researchers also tested whether nonpartisan German American voters were drawn to Trump's isolationist stances on issues such as opposition to the Iraq War and participation in international organizations. Analyzing data from the Cooperative Congressional Election Study, they established that in German-dominant counties, individuals with non-interventionist and economic protectionist views were likely to vote for Trump even without identifying as Republicans.

Individuals who opposed American involvement in United Nations military operations were also particularly likely to back Trump, they found.

The isolationist preferences of many German Americans stem from the group's historical experience, which the researchers said reverberated from the early 20th century to 2016. They noted that the group's isolationist tendencies have followed partisan and nonpartisan pathways since the years surrounding World War I. 

Following America's entry into World War I during Democratic President Woodrow Wilson's administration, many German Americans defected between 1916 and 1920 to a Republican party that promised increasingly to withdraw from European and other international flashpoints, a swing that the researchers found remained statistically predictive of German American Republican support in 2016.

Even non-Republicans were drawn to isolationist politics as a result of the war, they observed, noting that among large European immigrant groups from the 19th century, only German settlements supported Progressive candidate Robert La Follette's presidential bid in 1924. La Follette ran in large part on an isolationist agenda.

On top of their empirical evidence that German Americans were more likely to back Trump if they opposed American participation in United Nations military operations, the researchers wrote, the historical record suggests that the "remaining isolationist impulses could indeed be connected to the German American war-time experience."

Taken together, the researchers said, the study shows how German Americans have carried forward a distinct political orientation shaped by the turbulence of the 20th century, which should prompt future researchers to take the complexities of white ethnicity into account when examining political behavior.

"In contrast to analyses that see Trump as an expression of a 'white backlash,' we think that he had to appeal to various white groups with different offers," Hünlich said. "Racism was one of them, but it is not the driving force behind the German American vote."

"Team Trump knows the German American community and the particular appeal of isolationism in [this community]," he added, explaining that different rhetoric was deployed to attract voters from other ethnic backgrounds.

"If you look at other races[,] Trump's attempt to make custom-tailored political offers to ethnic groups is less surprising: Cuban Americans in Florida do not vote like other Hispanics, for instance," Hünlich continued. "Trump knew that and was able to reach them with his anti-Communist rhetoric."

But isolationism has a broad and potentially potent constituency in the U.S., and while neither party has a monopoly on it, the researchers noted, Republicans' recent turn against international intervention could give them an electoral boon going forward.

"There is a new brand of outspoken anti-war Republicans, such as Rand Paul and Matt Gaetz, that will follow after Trump," Hünlich said. 

"Whether it is by chance that they all come from German American families or not, if the anti-war narrative becomes a new Republican trademark, the Democratic Party faces a problem not only with German American voters," he added, noting that African Americans and Hispanics are also traditionally less in favor of interventionism abroad.

Whatever its consequences down the road, the researchers said it's clear that Americans of European ancestry shouldn't be analyzed as a monolithic political bloc or undifferentiated "melting pot," even decades and centuries after their arrival in the country.

"The link between politics and ethnic self-identification … is not meaningless," Hünlich said. "These [ethnic] labels stand for very different experiences of migration and integration."

"History matters," Gschwend said. "What happened during the realignment about a century ago still has political consequences today."

The article "A swing vote from the ethnic backstage: The role of German American isolationist tradition for Trump's 2016 victory," published Feb. 26 in Electoral Studies, was authored by Klara Dentler, University of Mannheim and GESIS - Leibniz-Institute for the Social Sciences; Thomas Gschwend, University of Mannheim; and David Hünlich, IDS - Leibniz-Institute for the German Language and University of Osnabrück.