>population of Vienna in the 16th century
maybe 50k, most sources say less

>population of Burgenland in the 16th century

>number of Croats settled to Burgenland in the 16th century
fucking 100k according to German Wikipedia.
https://de.wikipedia.org/wiki/Burgenlandkroaten

Sure, a part was killed in the battles with Turks, a part keeps larping as Croatians to this day, but this would be like settling 4 million Croatians around Vienna today, you cant not think a shitton of those did not get germanized to make heutigen Austrians