During the final push of World War I, U.S. and French troops were racing to liberate the French city of Sedan, and the U.S. commanders allowed some units to maneuver around each other in the closing moments to hit German lines. In the chaos, U.S. troops with the 1st Division arrested what they thought was a German officer, maybe even the Crown Prince of Germany, who actually turned out to be a famous general and hero.
(N.Y. State Military History Museum)
For this story, it's important to remember that World War I ended without Allied troops reaching German soil (something that Gen. John Pershing and Marshal of France Ferdinand Foch protested as they believed it would lay the seeds for another war). So, the final clashes took place on French soil, and there was a surge in fighting in the last days as Allied powers attempted to put as much pain on Germany as possible.
On November 6, this push reached the city of Sedan, and the 84th Infantry Brigade managed to push into the suburb of Wadlaincourt. The 84th had been battered by intense frontline fighting in the previous weeks, but its intrepid commander had fought from the front the whole time.
Brig. Gen. Douglas MacArthur had already been nominated for his fifth and sixth Silver Stars, both of which he would later receive. He had suffered injuries in a poison gas attack, survived artillery bombardments and machine gun attacks, and led his men to victory in key terrain.
Then-Brig. Gen. Douglas MacArthur in World War I.
(N.Y. State Military History Museum)
On November 6, he was in Wadlaincourt with his men, taking the fight to Germany even though few brigade commanders would've risked being that close to the guns.
And the 1st Infantry Division didn't know he was there. So when 1st Infantry soldiers saw MacArthur, clad in his grey cape and cap, they thought it was a German officer they were looking at. As Raymond S. Tompkins wrote in 1919 in The Story of the Rainbow Division:
All [the platoon leaders] saw in the gathering dusk was an important looking officer walking around, attired in what looked like a gray cape and a visored cap with a soft crown, not unlike those the Crown Prince wore in his pictures.
Yeah, coincidentally, MacArthur's common outfit on the front just happened to be similar to the Crown Prince of Germany's. While none of his own men would mistake the general for anyone else, he was not yet famous enough to be recognized by average members of other units.
And, the German Crown Prince had, in fact, led troops in combat in 1918 on Germany's Western Front. So it is, perhaps, not so surprising that the mistake could happen on a fast-moving and chaotic front.
The Crown Prince of Germany Rupprecht did lead German troops in the field against his nation's enemies.
(U.S. National Archives and Records Administration)
And so the patrol arrested him, and MacArthur protested his innocence and identity, but the platoon leader wasn't going to take the word of a probable German officer over his own eyes, so he vowed to take the man to a unit headquarters for identification.
Obviously, the 84th Infantry Brigade headquarters was nearby, since MacArthur was typically found close to his place of duty. So the 1st Infantry Division patrol took him there, to his own headquarters, for identification. Perhaps in a failure of imagination, his headquarters immediately identified him. They really missed a chance at a great prank, there.
It turned out well for them, though. The Armistice negotiations would begin days later on November 8, 1918, and was signed in the wee hours of November 11. MacArthur was made the division commander of the 42nd Infantry Division. He and his men were welcomed back to the U.S. as heroes, and it doesn't appear that MacArthur held any personal grudges against the 1st Infantry for his short detainment.