So my Grandfather was a Romanian man who spoke 7 different languages. I know that he fought or was used by the Germans during the Second World War. He never spoke about his past to my father and I was wondering if anyone could tell me what he might have been put through or might have done.
Thanks for any information!
Romania was an ally of Germany. Romanians fought alongside Germany on the Eastern Front. So, it's not so much that he was used by the Germans as that he was a citizen of an Axis country that had allied itself with Germany. Romanians fought all over the Soviet Union, and they were also involved in some of the worst excesses of the Holocaust, but it's impossible to say what your grandfather might have done without more data.
As /u/estherke pointed out, Romania was an ally of Germany, so most likely he fought as a Romanian soldier. But there was an SS unit composed of Romanian volunteers, so its possible he might have fought in a German uniform.
If you want to find out his military CV contact the Deutsche Dienststelle (WASt).
They have all the data about military and para military formations of the third reich.
When you know the units he was assigned to you can go and look up what they did etc.