My grandfather’s family lived in a village of Germans in what is now Serbia. He has always told me that the emperor invited them to settle there after the Ottoman occupation ended. As I’ve grown up and learned more about the region and its conflicts, I’ve started to suspect that the reasons were less innocent than that. Was the empire trying to make the area more German? Was it a case of ethnic cleansing? The village was called Molledorf, by the way, but it doesn’t exist anymore.
First things first, where exactly was Molledorf? Fortunately, we know exactly where Molledorf was because it's Serb name of Molin lends itself to three notable things - the local forest, the local prison camp and the flood that wiped Molin off the map.
Molin was located just to the north of Banatsko Karadordevo, in between the larger settlements of Kikinda and Zrenjanin and was set up in the 1830s by settlers moving into land provided by Count Ferenc Zichy-Ferraris (more on him in a bit). Within 15 years of being set up, it was a reasonably thriving town of 2000 before it got flooded for the first time - at this point, in 1870, Molin was more or less abandoned before being rebuilt higher up and many of the settlers moving back.
Much of what we have about Molin is, of course, about it's end rather than its start so to touch on that, after the fall of Austria-Hungary, there were suddenly a lot of settlements in the Banat (which is this region of Serbia) which were suddenly part of a new nation. Molin itself was a mixed settlement of Germans and Hungarians and, as such, prime for the nostalgia of a former empire that was channelled into the kulturbund, set up in Novi-Sad originally as just a Austro-Hungarian cultural charity but, as the Thirties hit, swiftly turned into an organisation that combined the older generation of settlers pining for the old way and the younger generation upset with the new way. In short, they became Nazis - some estimates (Jelena Popov's) make it that 95% of German settlers in Yugoslavia were members of the Kulturbund. Come the end of WW2, most Germans left Serbia and some of those that didn't were sent to a prison camp in Molin, which operated between 1944 and 1947 as a halfway house between capture by Yugoslavs and to larger camps or (if they'd come that way) to the Soviets. Like many settlements, the houses Germans and Hungarians left behind were given to the native population (specifically Serbs in Molin) but in 1956, the settlement was flooded again and it was soon abandoned.
It's worth noting that Molin was built in a really stupid place - in a depression with shallow groundwater meaning that, while it wasn't near a river, it was very easily flooded as this paper would posit.
Back to the start and to the Zichy family. Ferenc (born 1811 - there's a few Ferencs in the family!) was pretty notable by himself - an ambassador to the Ottomans, adviser to the Russian army, head of the local railway, etc. After the first phase of immigration in the 18th Century, swathes of land in the Banat was auctioned off to be bought by, in this case, Jozef de Ferraris whose daughter married into the Zichy family and Ferenc was a big builder, creating multiple towns and complicated ownership structures. Molin came about as an extension of an earlier Zichy settlement of Herniethof and became populated not really by emigres from Germany but from those moving across from already established settlements who wanted land for themselves.
So, to your point of "was there anything suspicious about it", the likelihood is that your family were already in the region and that the ancestors that moved to Molin were young, poor and agricultural as opposed to participating in anything dodgier. Perhaps the greatest sign of the poverty of the village was that it never, at any point, had any roads connecting it to other villages. What it was more a sign of was 19th Century aristocratic opportunism rather than anything more sinister than that (albeit, if there's any information on where they came from prior to Molin given it's extremely unlikely that's the first place they landed, that's up for consideration!)
The village of Molidorf was founded in 1832 in an area called Banat. This was then southern Hungary, near the Serbia border. It is now in Serbia, but abandoned. The name is also written as Molledorf (German) Molin (Serbian) and Molyfalva (Hungarian).
After the Ottomans lost the territory, there was a deliberate attempt by the Austro-Hungarian Empire to move Germans into Banat and close regions. This is called the Great Swabian Trek, as many of the Germans were from Swabia. This mostly happened from 1711-1780. Molidorf was founded somewhat later in 1832. Most of the original residents of Molidorf came from surrounding ethnically German villages in the Banat area: St.Hubert, Charleville, Soltur, Heufeld, Massdorf,Hatzfeld, Bikatsch, and Novosel.
I am glad your family moved out of Molidorf and were spared the later atrocities.
http://www.molidorf.org/History.htm
https://feefhs.org/region/banat-finding-village-of-origin
https://www.dvhh.org/history/atrocities/chap_3_tito_1944-48-N-banat.htm
https://www.blackseagr.org/learn_hungary.html
https://www.grhs.org/chapters/gdo/GermanyHungaryRussia-2007.