Dear Pan Alexander,
I see your many years efforts to preserve family roots, and to find the homeland of your ancestors from this part of United Europe, please find my help from Poland:
I. Your first problem is the search with family name, not all search engines could help, as your MANKA is correctly spelled in Polish as MAN~KA - with Polish grammar diacritical mark as accent over the letter. Here is for you the base info with Polish etymological works:
MAN~KA > This old Polish surname is patronymic in origin, and derives from name Mank, and/or the first name Manomir, Manilo, and/or from the Germany language, and name Mahnke - finally, the Polish and Catholic surname was ended as Man~ka.
II. I cannot say that your family was Germans all repatriated to Germany after the WWII like almost all Gemmans from this area of Poland (in the 19th belonged to Prussia/Germany - on the border of Russia/Poland). Your family supposingly was Polish, with RC religion, and some of wealthy part families in the village - why? I'll try do explain it to you in a few words: their first names were not tipical for poor peasants (Anna, Karol, Julianna were tipical for wealthy families), their parents' occupation and property give them chance to send three young daughters to America, after that the descendants possibly sold home/land(s) in this Brodnica, and settled in near town.
Your ancestors' Caroli seems is in Polish Karol, Anna, Julianna, Maria, Marianna all were tipical Polish, not German.
III. The final question is the right location of the family homeland and parish. Yes, there is also village KARBOWO located between Orneta and Lubomino, but my guess is that your family KARBOWO is located just in one kilometer in North of the town BRODNICA, in the same area.
Here is the traces from the Polish censuses 1990/2009, and Polish phone directories:
In this village KARBOWO n/BRODNICA they are not living any families surnamed MAN~KA or KOZLOWSKI, but in this near very old Prussian/Polish town BRODNICA are still living:
1. Andrzej Man~ka, Brodnica, Poland
2. Halina Man~ka, Brodnica, Poland
3. Piotr Man~ka, Bordnica, Poland
4. Roman Man~ka, Brodnica, Poland
5. Urszula Man~ka, Brodnica, Poland
18 people surnamed KOZLOWSKI in this Brodnica.
Be careful with BRODNICA, there are three places in Poland named Brodnica, and your is here on the detailed map of Poland:
Thus, here is the family ancestral church/parish and town's webpage:
A propos the ancestral church: Polish historical dictionary is telling about your grandmother's place of birth and childood, from "Slownik Geograficzny Krolestwa Polskiego...", t. III, page 834:
"Karbowo, located just a half mile of the town Brodnica, counted in abt yera 1880 - 13 homes, 325 Catholics, and 109 Evangelics, having post and church/parish in Brodnica, school in near Zmijewo, this Brodnica is the wealthiest property/farms in the area, belongs to Kryger, having also the distillery based on very modern steam machines".
Finally, here is for your FAMILY MANKA HISTORY BOOK the image of the family ancestral church, where all ancestors were baptized, married, and burried on the local cemetery at this church:
Good luck in your search,
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