Multiple given names is hardly limited to nobility. Once surnames were established certain given names and surnames became extremely common. For a non-noble, such a name as "Johann Schmidt" or "Kovacs Janos" (the latter using the Hungarian pattern) could get confusing if someone with such a name went to the big city.

Eventually families named Schmidt started using such patterns as "Johann Georg Friedrich Wilhelm Martin Schmidt", assuming that enough given names can differentiate almost anyone. One of the given names was usually a saint's name, so that practically ensured 365 possible variants where one of the names reflected the saint's day which was also the child's birthday. To be sure, so plebeian a surname as an occupational name or a patronymic (Scheider, Peters)created problems without multiple given names -- but imagine the situation for nobles! There would be plenty of Habsburgs, Wittelsbachs, and the like, coming into contact with each other. Mobile as nobles were they would need multiple names in Europe. The patterns differed by class and nation, so far as I can tell.

The pattern differs greatly from that in America, at least in small towns. America was a nation of small cities as late as 1800 -- even the largest of American cities were small enough that there might be one "John Peter Williams".