Who were the neighbors of the Salian Franks who lived in the 4th largest city in Germany?
Salian Franks:  They are contrasted with their neighbours to the east, the Ripuarian Franks, whose capital was in Cologne. Cologne: Cologne ( ; German: "Köln" , ] , Colognian: "Kölle" ] ) is the largest city in the German federal State of North Rhine-Westphalia and the fourth-largest city in Germany (after Berlin, Hamburg, and Munich).
Ripuarian Franks