Originally Posted by
Stearsolina
^^^I can say how it was with Danube Swabians in Slavonia (eastern Croatia).
They lived in separate, fully German villages, and they did not mix either with Croats, neither with Slovaks or Hungarians, let alone Serbs or Rusyns. Despite of being Catholic. They were very closed rural community and many never even learned Croatian language. However, there were many Germans (some children or grandchildren of these Danube Swabian settlers) who went into bigger cities like Osijek (Esseg) or Zagreb (Agram) and those were assimilated, mixed with Croats, Magyars, Czechs etc.
Rural Swabians were even kind of ghettoized population, they lived with other Germans, spoke German and kept to themselves. During WW2 many of them joined the SS and they felt completely German.
After the war many were murdered in concentration camps and some fled, and those who survived were deported to Austria and west Germany.
It affected rural Swabians the most, entire villages were emptied, while urban Swabians who were often much more mixed and assimilated remained. Most of German ancestry in eastern Europeans is from such mixed people while those "real" and unmixed Germans left or were expelled. This is only way to explain why are they still heavily west German genetically today, after centuries in foreign lands.
In Hungary assimilation was greater, but still what I described applies. Rural Swabians were pretty much Germans until 1945, even politically. It's city and townsfolk people who mixed and assimilated, villagers not really.
Representatives of Transylvanian Saxons also supported unification of Transylvania with Romania against Hungarian interests.
During WW2 Banat was directly occupied by Germany and did not re-joined to Hungary. I assume local Germans preferred it so.