In the geopolitical conflict over the South China Sea (SCS), fishers are at the center of Chinese and Vietnamese cartographic imaginations that define the sea as either “Chinese” or “Vietnamese” and hence tied to the disputed territories of the Paracel and Spratly Islands. While their historical presence and customary fishing rights in the SCS have been much publicized in the context of this territorial dispute, the long-standing Cham seafaring trade networks and legacy are ignored by both countries. The ethnic and national categories of Cham, Việt, and Han intersect with occupational categories such as those of fisher, trader, shipbuilder, sailor, and pirate, which in the past represented shifting, relational, and situational activities by the same people. The contemporary use of such professional and national labels produces particular political effects by projecting recent closures and enclosures onto the past, in spite of the common historical, cultural, and ethnic flows that always existed in the SCS. Rather than aiming to legitimize or delegitimize Vietnam’s or China’s territorial claims to the SCS, this article argues that seafaring narratives should be liberated from abstract, anachronistic discourses of sovereignty, territoriality, and territorial anxieties that separate the interconnected histories of the Cham, Vietnamese, and Chinese.