This study examines the parallel yet highly divergent careers of Hans Hass and Jacques-Yves Cousteau, two central pioneers of twentieth century underwater exploration. While both contributed substantially to marine science, diving technology, and the visual mediation of the underwater world, their long-term global recognition developed in markedly different ways. Drawing on diverse interdisciplinary perspectives, the article explores how geopolitical conditions, institutional support systems, narrative self-presentation, and the rise of a global media ecology shaped their public visibility. Beyond a biographical or technical comparison, the juxtaposition of Hass and Cousteau is deliberately employed as a conceptual case study to examine the formation of maritime memory in twentieth century underwater research. The findings demonstrate that Cousteau’s worldwide prominence resulted not solely from scientific or technological achievement, but from his exceptional integration into powerful institutional, technological, and cultural infrastructures that amplified and internationalized his work. In contrast, Hass - despite significant early innovation and ecological awareness - was constrained by weaker institutional embeddedness, a scientifically restrained and emotionally neutral serial television aesthetic with limited long-term repeatability, and subsequent theoretical isolation. A decisive factor in this divergence was Cousteau’s entrepreneurial engagement with emerging television markets, which transformed underwater exploration into a scalable media enterprise and provided the structural basis for his enduring visibility. Overall, the analysis suggests that maritime memory is shaped less by scientific merit alone than by the ways media, politics, and economic scalability stabilize certain cultural narratives. These dynamics have produced asymmetrical legacies that continue to shape how ocean exploration is remembered and imagined today.