Earlier quoted context omitted.
> Homogeneous in the modern use What does it mean if it includes heterogenous populations from linguistic, historic, religious and even cultural backgrounds?
I think they mean racial/ethnic.
"In early modern Switzerland, the Swiss Confederacy was a pact between independent states within the Holy Roman Empire. The populations of the states of Central Switzerland considered themselves ethnically or even racially separate: Martin Zeiller in Topographia Germaniae (1642) reports a racial division even within the canton of Unterwalden, the population of Obwalden being identified as 'Romans', and that of Nidwalden as 'Cimbri' (viz. Germanic), while the people of Schwyz were identified as of Swedish ancestry, and the people of Uri were identified as 'Huns or Goths.'
Modern Switzerland is atypical in its successful political integration of a multiethnic and multilingual populace" [1].
I know plenty of Swiss-for-generations Swiss whose complexions would not have passed as white a hundred years ago.
[1] https://en.wikipedia.org/wiki/Swiss_people#Cultural_history_...