Dr. Erich Kästner is, at age 107, the last known German veteran of the First World War, and a combat veteran for that matter, and currently the second-oldest man in Germany (the oldest one did not serve). The second-to-last known German veteran of that particular war, William Seegers, passed away July 10, 2007. Kästner joined the army in July 1918 in the "Sonder Bataillon Hauck", and served on the Western Front. Wikipedia
The definitive Wikipedia entry for Erich Kästner. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Erich_K%c3%a4stner_%28WWI_veteran%29