Until the mid-1950s nearly all the waters lying between the far-flung islands of the Indonesian archipelago were as open to the ships of all nations as the waters of the great oceans. In order to enhance its failing sovereign grasp over the nation, as well as to deter perceived external threats to Indonesia’s national integrity, in 1957 the Indonesian government declared that it had “absolute sovereignty” over all the waters lying within straight baselines drawn between the outermost islands of Indonesia. At a single step, Indonesia had asserted its dominion over a vast swathe of what had hitherto been seas open to all, and made its lands and the seas it now claimed a single unified entity for the first time. International outrage and alarm ensued, expressed especially by the great maritime nations. Nevertheless, despite its low international profile, its relative poverty, and its often frail state capacity, Indonesia eventually succeeded in gaining international recognition for its claim when, in 1982, the United Nations Convention on the Law of the Sea formally recognized the existence of a new category of states known as “archipelagic states” and declared that these states had sovereignty over their “archipelagic waters”. Sovereignty and the Sea explains how Indonesia succeeded in its extraordinary claim. At the heart of Indonesia’s archipelagic campaign was a small group of Indonesian diplomats. Largely because of their dogged persistence, negotiating skills, and willingness to make difficult compromises Indonesia became the greatest archipelagic state in the world.