Diplomacy relies on personal mobility and interstate networks that connect lower-level interactions with high-level engagement. Although their effect on negotiations, alliances, and wars is evident in political history, the mobility and networks of ancient diplomacy often escape attention. Adopting an archaeological perspective, this chapter examines the political landscape of Archaic to early Hellenistic southern Italy and Sicily by tracking the routes of kerykeia, portable diplomatic insignia. Around fifty known staffs are analysed, with inscriptions used to identify home communities and findspots helping to reconstruct itineraries. These movements are set against the period’s political upheavals, paying particular attention to the Italic polities in southern Italy and Sicily as they entered the diplomatic arena. The resulting picture enriches the historical account of interstate actors, complicates the relationships between Greek and non-Greek communities, and demonstrates how people, objects, and information circulated throughout the central Mediterranean, manifesting and maintaining network ties through mobility.