Why did two families from neighboring Prekmurje villages report such different languages and identities around 1900?
I am researching two separate families from a small cluster of villages in northern Prekmurje, then part of Vas County in the Kingdom of Hungary. The main places are Ropoča, Pertoča, Adrijanci, and Šulinci, with later connections to Lucova and Čepinci.
The first family, the Donosas, had a local South Slavic surname and roots in Ropoča and Pertoča, but the emigrant generation repeatedly identified as Hungarian or Magyar. One member lived in Graz. Another married a woman from Vienna who identified as German, while he identified as Magyar on the same record.
The second family, the Balleks, came from Adrijanci and Šulinci. Their records are much less consistent. Some members reported Hungarian as their mother tongue. In one census, Hungarian was entered and then changed to German. Other close relatives were identified as Slovene. One emigrant was first classified as Slovak, then corrected to Slovene, while his language was recorded as Croatian.
How should this contrast be understood in the social and linguistic context of northern Prekmurje around 1880 to 1914?
Were differences like these likely to reflect actual variation between households and siblings, or are they more likely to be artifacts of immigration and census record-keeping?
What factors, such as schooling, religion, occupation, marriage, military service, or migration through Graz and Vienna, most strongly shaped whether someone from this region identified as Magyar, Slovene, or German?
I would also appreciate recommendations for scholarship on everyday language use and identity in Prekmurje or western Vas County, especially work that goes beyond official census categories.