John
Where are you finding records for John and Catherine? I find them in no census records in PA, nor any other records under either spelling. Nor do I find them in the PA marriage records available at FamilySearch.com
Also be aware that in the northern part of what is today Serbia is a place called Sombor, which was under the rule of Austria-Hungary... and that many ethnic Germans lived in this area.
http://www.dvhh.org/batschka/village/Zombor.htmRobert Jerin
Croatian Heritage Museum
Cleveland Ohio