I think the main language was English, we even had some lovely Americans in the group who were such great fun to hang out with. You wouldnt have any troubles with the language in german, usually everything is translated too.
That's pretty cool. Did the American's make the trip special to be there or were they expats that had moved to the area? It's cool that you got to spend some time with them either way.
I think they were visiting Hamburg and flew in, but not directly from the US. Yes it was great to spend some time with them, it was such good fun, they were part of the hardcore gang and stayed til the end!