This paper explores the intricate interplay of science, strategy, and technology in shaping the Mediterranean Sea's territorialization in the early 20th century. Inspired by the ERC-CoG DEEPMED project, the study unpacks the Mediterranean as a space of promise, examining the clash between visible and submerged everyday technology and the interplay between deep-water knowledge and transnational border drawing.

Examining the construction of early 20th-century submarine telegraph cables between Italy and Libya, the paper explores critical questions about colonial legacies embedded in cable construction and their impact on native societies and Italian colonial policies. It scrutinizes the role of the telegraph in the establishment of racial discrimination in Libya, contributing to understanding knowledge production and power relations in the colonies.

The Italo-Turkish war of 1911-12 then provides a trans-imperial perspective on the use of telegraph submarine infrastructure, opening discussions on power relations between colonial empires and private companies and shedding light on Ottoman-British-Italian cooperation, rivalry, and competition.

The study delves into the dynamics of experts, employees, and knowledge production, including native workers' surprising involvement in skilled cable technician roles. The cable's perpetual malfunctioning state and challenges in underwater construction further entangled technology, labor, and the sea. The paper adds to the literature on history of marine infrastructure and environment, arguing that the element of deep-water both hindered the potential for resistance (sabotage of infrastructure becomes harder if it is underwater), while at the same time complicating colonisation, as the traditional tools of such enterprise (i.e., mapping) became less efficient underwater.

Ocean historians often emphasize the fluid opacity of oceanic matter, processes, and geographies. Yet, counter-narratives rigorously assert the situated historicity of ocean places, and further, the potential of ocean histories to usefully re-situate and reframe staid interpretations of migration, technological exchange, and development. This paper intervenes in this conversation within the history of ocean science & technology, outlining a history of ocean thermal energy conversion (OTEC). OTEC is a process for generating usable energy by exploiting a thermal gradient between surface and deep seawater. Because of its reliance on steep thermal gradients, scientists and politicians have often pointed to islands with narrow littoral zones--including Cuba, St. Croix, and Puerto Rico in the Caribbean, and Nauru, Hawaii, and Japan in the Pacific--as sites for its potential implementation. OTEC’s history is bound up with other mid-20th century extractive frontiers including deep-sea mining, as well as histories of American and Japanese empire. Despite hopes (ranging from the neocolonial to the postcolonial emancipatory) that OTEC might generate limitless electricity within and beyond islands, OTEC has largely failed to become scalable. Instead, OTEC pilot projects have cultivated new attachments and anxieties. This paper combines a history of OTEC development and implementation with ethnographic encounters at the Natural Energy Laboratory of Hawaii to address two questions: What have OTEC pilot projects, in the absence of generating power, been for their boosters, clients, and host sites? And, what might historicizing OTEC do for stories of empire, scientific development, and the future, as told from seawater?

Conversations concerning the twentieth-century global shift to two hundred nautical mile exclusive economic zones often focus on the horizontal push outward of national maritime boundaries and international conflicts over fisheries and national security. However, America’s unilateral claim to the continental shelf and the vertical push downward of national maritime boundaries present a compelling case study for exploring the role of industry knowledge production in shaping ocean governance. American approaches to marine policy were adopted internationally and demonstrate the influential place of petroleum geology in the history of global geopolitics. Most notably, how marine geology and geophysics expertise moved from the halls of Congress to the United Nations. The United Nations Convention on the Continental Shelf in 1958 and later negotiations on the Law of the Sea agreed that coastal nations should have sovereign rights to explore and exploit their continental shelves. The UN also redefined the continental shelf in ways that reflected American legislative negotiations and language, which differed from existing geoscientific definitions outside industry influence.

Regulatory capture wasn’t just about money; it was also about knowledge production and the sciences that influenced how decision-makers understood and valued certain environments. This analysis aims beyond existing narratives of regulatory capture to interrogate how extractive industries employed environmental access and knowledge as a geopolitical tool. It also demonstrates that ocean history isn’t just about oceans. This approach has implications for better understanding environmental value, expertise, and environmental decision-making across ecosystems.

Colonial maps have long been used to assert colonial law. In the British colonisation of Australia, cartography is used to represent two violent fictions: the ocean as empty of law (aqua nullius) and gateway to an empty land (terra nullius). In the context of the Southern Ocean, these legal fictions are represented in 18th century navigational maps as well as contemporary bathymetric charts. While early navigational maps legitimised the brutal and unlawful invasion of Gunditjmara Country, the use of bathymetric mapping in the 21st century expanded this colonial imaginary below the surface of the ocean with the seabed itself represented as a space of oil and gas production.

Connecting Dutch and English colonial maritime maps to the contemporary use of state-sponsored bathymetry, this paper argues that, in the context of the ongoing colonisation of Australia, mapping practices give form to colonial legal relations. In colonial maps the ocean is represented as a frontier; an empty space to access resources and/or commodity to be exploited. In both representations, unceded Indigenous sovereignty is violently removed from the map.