Here’s what you will learn when you read this story:A figure in a photograph of an infamous WWII massacre known as “The Last Jew in Vinnitsa” has long gone unidentified. Jakobus Onnen, a former teacher and member of Einsatzgruppen C, has been identified as the Nazi gunman who posed for a photo during a massacre at the citadel of Berdychiv. But one historian has spent years trying to determine the identity of the man holding the gun—the cold-blooded, bespectacled killer in the infamous image. Now, thanks in part to AI-assisted analysis, the gunman has likely been identified as Jakobus Onnen, a teacher from Tichelwarf. That Jakobus Onnen is the man photographed holding the gun is no longer in dispute for Matthäus.