My father was lucky enough to serve in Germany during the Korean War. In 1953 he attended a seder in Munich. It was held in a huge hall where Hitler had spoken. He has spoken to us (his many children) many times about this seder and wishes he had kept the Hagaddah or had some kind of photograph. There were hundreds of people in attendance, most of them American military. There must be people out there with photos and memories. If you are one of them, please share your memories.
Here are some links to accounts of other seders held after the war:
The Historical Seder in Munich, April 15-16, 1946