Künstler died in Niederstetten in the German state of Baden-Württemberg from complications of a gastrointestinal operation and a broken femur, his family told German celebrity magazine Bunte.
An ethnic German born July 24, 1900 in what is now Soost, Romania, Künstler fought for the the First World War for the Austrian army in Italy. He was the last known German WWI veteran.
Künstler had lived in Niederstetten since 1946 and worked as a guide in a hunting museum at a local castle, Haltenbergstetten.