These Germans called Transylvania: Siebenburgen, and they were ordered to evacuate in September of 1944. They would go back to a part of Germany which was "considered" safe for them. Most if not all of these Germans had never lived in Germany and most had never travelled this far in their lives.
The point was that the war was being lost by the German Army, and unlike during the Great War, the Germans who lived outside the borders of Germany for hundreds of years, were ordered to leave what they considered their homeland, that being Siebenburgen or Transylvania.
Over time, some would return, but most would not. These days many of their descendants return for tours of the lands that their parents and grandparents, and even great-grandparents lived.