At the time of Roger II's coronation other Latin princes – including certain of his subjects – had no reason or desire to regard his position as permanent. The German rulers were naturally glad to see Byzantine and Arab power in southern Italy extinguished; they still hoped that the Normans would prove to have done no more than to prepare the ground for their own take-over, based on a historic and rightful claim to possession. Similarly, Byzantine and papal claims to practical or theoretical overlordship were reactivated. All this seriously compromised the interests of the north Italian republics – their commercial interests in Sicily and in Constantinople, and their defensive interests in northern Italy, where they were exposed to German attack. The alternatives were clear, and none was without its lure. The republics could defend imperial claims to southern Italy by providing the Germans with a fleet, in return for commercial concessions in conquered territory – a line held to by Pisa with fair consistency. They could offer Constantinople similar services – as did Venice, in order to protect one side of its Adriatic trade, though at the same time the city had deep commitments in Norman Apulia. Or the republics could place their interests in the Regno first and hope thereby to win the gratitude of the Sicilian kings, along with commercial privileges – a gamble the Genoese took as far as they could.

Shortly before Roger II's fleet sailed into Salerno in summer 1127, the Pisans made a treaty of friendship with Amalfi that provided both sides with shops and warehouses in each other's city, as well as the right to trade free from tolls and taxes.