My parents, after having German tenants for several years, adopted some of those traditions for Christmas Eve dishes. My mother, being from a family that came from Sweden to Duluth (I know, what's the point of moving from Sweden to "Sweden"?), had a number of Swedish dishes already on the menu.
One thing in particular that I haven't seen mentioned anywhere here on Chowhound, is a wonderful potato salad with pickled herring and dry salami that was introduced by our German friends. There was also something called "karvedunce", a dish along the lines of pate en gelee.
I think it must have been "kalve" or calf/veal.
Cookies were also a big part of that meal. My mother made fatigman (sp?) which were fat men - dough cut in a shape and deep fried, then dusted with powdered sugar. She also made pecan balls, the most delicious cookies I've ever eaten. I'm sure they were 1/2 butter.
We've heard of the Italian loads of fish tradition on this board, how about some others?
Also, if anybody has heard of or knows a recipe for that potato salad, I'd love to have it.