Although “peace on earth” may never have seemed more elusive than during the Civil War, America’s bloodiest years actually produced our popular image of Santa Claus.

Clement Clarke Moore had injected Santa into the American psyche with his 1823 poem “A Visit from St. Nicholas” (more popularly known as “The Night Before Christmas”), but it was four decades later when the modern-day figure of St. Nick was first outlined by the pen of noted illustrator Thomas Nast.

The political satirist, who later gained fame parodying both political parties by drawing an elephant as a symbol for Republicans and a donkey for Democrats, joined the staff of Harper’s Weekly, one of Civil War America’s most widely read periodicals, in the summer of 1862. A fervent supporter of the Union cause, Nast had considerable experience illustrating Abraham Lincoln, but another bearded figure, Santa Claus, was his subject for the cover of the magazine’s January 3, 1863 issue.

Nast, who had emigrated from Germany with his family when he was six years old, tapped his boyhood memories of St. Nicholas to sketch a Santa with a reindeer-drawn sleigh, long white beard and fur-lined hat and coat visiting a Union army camp. Nast’s Santa isn’t decked out in red, however, but a star-spangled outfit featuring red-and-white striped pants and a blue jacket with white stars. Nast enhances the patriotic setting by drawing soldiers firing an artillery salute, the Stars and Stripes flapping proudly in the breeze and a triumphal arch decorated with evergreens that says, “Welcome Santa Claus.”

Sitting atop his sleigh, Santa hands out gifts that include stockings and meerschaum pipes and a jack-in-the-box for a pair of young drummer boys who sit playing in the snow. Santa is clearly not wishing goodwill to all, however, for in his hands is a dancing puppet of Confederate president Jefferson Davis with a string tied around his neck that makes it appear as if he is being lynched by St. Nick. “Santa Claus is entertaining the soldiers by showing them Jeff Davis’s future,” expounded Harper’s Weekly. “He is tying a cord pretty tightly round his neck, and Jeff seems to be kicking very much at such a fate.”

Nast drew less belligerent depictions of Santa Claus inside the same edition of Harper’s Weekly. One lavish illustration depicts a lonely Union soldier on Christmas Eve 1862 sitting by a flickering campfire gazing at photographs of his family while back home his wife kneels with her hands clasped in prayer wishing for her husband’s safe return as moonlight illuminates their cherubic children asleep in bed, dreaming of Santa. The two-page spread includes images of battlefields and tombstones, but also of Santa climbing down a chimney and being swept through a Union campground by his reindeer as he tosses presents out of his sleigh.

Santa became entwined with in the Confederacy as well during the Civil War. Wartime shortages brought austere Christmases, which required explanations about Santa’s absence. Some parents explained that the Union blockade had prevented Santa from traveling to the South, while a slave even played the ultimate Scrooge by telling a family of children in Georgia that St. Nick had been shot by the Yankees. The Richmond Examiner even told Virginia that, no, there wasn’t a Santa Claus. The newspaper blasted St. Nick as “a Dutch toy-monger” and “an immigrant from England” who had nothing to do “with genuine Virginia hospitality and Christmas merry-makings.”

Over the next two decades, Nast’s early woodcuts of Santa Claus crystallized the modern-day image of a hefty, jolly Kris Kringle with a long white beard and red outfit. However, the Civil War would not be the last time that Santa was enlisted for the war effort. During World War I, Santa was transformed into a patriotic figure along the lines of Uncle Sam as the U.S. government produced advertisements and artwork that showed Santa with the troops and hawking war bonds.

When World War II came to the United States with the bombing of Pearl Harbor just weeks before Christmas 1941, Santa Claus was again deployed to help with the war effort. Santa urged Americans to buy war bonds, conserve resources and maintain silence to prevent leaks to the enemy.

He was also wrapped in more militaristic iconography. The War Production Board produced a poster of a jolly, gun-toting Santa with a rifle over his shoulder that blared, “Santa Claus Has Gone to War!” Gone is St. Nick’s familiar red suit and hat, replaced by a drab olive army uniform and helmet. Another War Production Board propaganda poster showed Santa along with airplanes and munitions with the tidings: “Merry Christmas to All and to All a Good Fight.”

A letter to Santa pledged that the weapons would be delivered to “Messrs. Hitler, Tojo & Mussolini.” It was a not-so-subtle attempt to use Santa to frame World War II as a conflict between good and evil, between naughty and nice.