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Though the sesquicentennial of his death will go largely unremarked, the German-American artist Carl Wimar died on Nov. 28, 1862, succumbing to the ravages of tuberculosis. Hardly recognized today, Wimar, like his mentor Emanuel Leutze, was an immigrant painter who found the promise and character of the American nation the perfect subject, even as that nation was being torn apart by war.

Though Leutze’s name and work were better known, the two worked in tight parallel. While Leutze created “Washington Crossing the Delaware” and decorated the Capitol building as it was being finished during the Civil War, Wimar finished his own magnum opus, comprising murals and frescoes, for the newly completed dome in St. Louis’s federal courthouse.

Wimar was born in Germany and immigrated to America when he was 15 years old. He returned to Germany, however, to attend the famous Düsseldorf Academy, where he first encountered Leutze. “Mr. Leutze paid a visit to me in my atelier, and brought along all the Americans who are here,” Wimar wrote excitedly in October 1854. The academy was the locus of German Romantic painting, and the key training center for American romantic artists as well — William Stanley Haseltine, Eastman Johnson and Richard Caton Woodville all passed through there. While in Düsseldorf, George Caleb Bingham, a renowned artist from Missouri, attempted his own version of Washington and his troops on the Delaware River; he also brought copies of Gilbert Stuart’s portraits of George and Martha Washington there to work on his commission for the Missouri state capitol.

Wimar showed some interest in history paintings, with both European and American subjects, but his true love was “Wildwestgeschichten,” or wild west stories. Wimar himself had never visited an American Indian encampment, but he filled so many canvases with buffalo and encounters on the emigrant trails that his colleagues called him “the Indian painter.” In the winter of 1858 and 1859, Wimar returned to America, finally ventured up the Missouri River and afterward stopped depicting imagined abductions. Instead he painted stark plains landscapes, rituals of the buffalo hunt and ethnographic portraits of American Indian leaders.

The commission at the St. Louis courthouse, however, was a chance to think broadly about American history, as seen from the center of the continent, in a border state bitterly divided by the Civil War. In this context, Wimar chose a telling narrative of the past, present and future American unity, one that emphasized the history of St. Louis for the success of the nation.

Wimar’s message balanced an argument about the centrality of St. Louis to American history with the needs of the nation at war. For accuracy of detail, he consulted Wilson Primm, a longtime St. Louis resident and author of an early history. Three panels, to the north, south and east, showed past highlights: the 1541 “discovery” of the Mississippi by the Spanish explorer Hernando De Soto, the 1764 founding of St. Louis by the French trader Pierre Laclède and a 1780 attack on St. Louis by Indian tribes allied with the British during the American Revolution.

Selecting a minor-to-forgettable skirmish from the American Revolution became a natural choice during the Civil War: the battle scene demonstrated when, once before, St. Louis had repulsed amassed forces comprising former friends and allies. By attaching his name to the federal courthouse, of course, Wimar was also making a political comment: that German-Americans would stand steadfast beside the Union.

Wimar’s work at the courthouse included allegorical figures of “Law,” “Justice,” “Liberty” and “Commerce,” as well as small portraits of George and Martha Washington, the former Missouri senator Thomas Hart Benton and Edward Bates, a conservative Missourian and former slaveholder who served as Lincoln’s attorney general. These were not random or incidental choices for Wimar. Each had a symbolic importance to his vision for America’s past and future, at his adopted city’s place within it. As the founding general and the first president, George Washington remained revered on both sides of the conflict; at Washington University in St. Louis and beyond, the image of Washington remained a symbol of national promise. Benton and Bates, local politicians, each had sought to prevent division over slavery through sectional compromise, and each played a role in promoting the uniting power of railroads.

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At the very top of the dome, Wimar’s fellow German-American artist August Becker continued the theme of reunification by marrying the agricultural products of the nation: corn and wheat, the leading produce of the North and Midwest, joining pineapple and sugar cane, icons of Southern hospitality and trade, to symbolize the reunited national harvest.

The return of national markets, the completion of the transcontinental railroad — Wimar painted images the resonated with the hopes of the Union in the continuing war, but that spoke to the timeless dreams of the American nation, as understood by a German immigrant. As part of his work at the courthouse he painted a large canvas titled “Westward the Star of Empire Takes its Way” — nearly the same title that Leutze gave to one of his works at the Capitol. But while Leutze painted a wagon train and the water entrance to California’s Golden Gate to symbolize the West, Wimar saw the future in Cochetopa Pass, Colo., “the natural gateway of the Central Pacific railroad,” which he dreamed would reach from St. Louis across the West to the Pacific.

Wimar wasn’t alone in his vision of St. Louis as the new heart of a postwar, reunited country. After the war another visionary, the journalist, Logan Uriah Reavis, called for St. Louis to replace Washington as the nation’s capital, perfectly balancing the interests of North, South and West. In the end, of course, neither his nor Wimar’s vision came to pass: the transcontinental railroad went farther north, through Chicago, Omaha and the basins of Wyoming, and the national capital remained in Washington, what Reavis called “a distant place on the outskirts of the country, with little power or prestige.”

Still, it is a vision worth recalling, both for its faith in the future of a nation made whole and its identification of the country’s vast middle as an unending source of wealth. Walking through the Old Courthouse today, part of the National Park Service’s Jefferson National Expansion Memorial, next to the Gateway Arch, one can appreciate the power of a space where Thomas Hart Benton called for a transcontinental railroad to unite the nation; where Dred and Harriet Scott filed their claims for freedom; where Virginia Minor argued for her right to vote, under the equal-protection clauses of the 14th Amendment — and where, in glorious images, Carl Wimar gave his last efforts to paint images of union during the Civil War.

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Sources: Adam Arenson, “The Great Heart of the Republic: St. Louis and the Cultural Civil War”; Rick Stewart, Joseph D. Ketner and Angela L. Miller, “Carl Wimar: Chronicler of the Missouri River Frontier”; Carl Wimar Papers, Missouri Historical Society; William R. Hodges, “Carl Wimar, a Biography”; St. Louis County Court Records, Jefferson National Expansion Memorial Archives; John H. Lindenbusch, “Historic Structure Report, Historic Data Section, Part I, and Historic Grounds Study, Old Courthouse, Jefferson National Expansion Memorial”; Logan Uriah Reavis, “A Pamphlet for the People: Containing Facts and Arguments in Favor of the Removal of the National Capital, to the Mississippi Valley.”

Adam Arenson is an assistant professor of history at the University of Texas at El Paso and the author of “The Great Heart of the Republic: St. Louis and the Cultural Civil War.”