The latter years of Spain’s neutrality during the war (1759–62) saw an even greater deterioration in Anglo-Spanish relations. Ministers from both Courts attempted to preserve and salvage Spanish neutrality, but unresolved diplomatic grievances, as well as the deaths of both the Spanish king, Ferdinand VI, and the British monarch, George II, foiled their efforts and any gains made by the case of the San Juan Baptista. The increasing decay and eventual breakdown of Anglo-Spanish relations during the war demonstrate that the tactics used to ensure Dutch neutrality could not so easily be transferred to maintain Spanish neutrality. This chapter begins with the appellate case of the Jesús, Maria, y José and a close look at the legal arguments presented for both the Spanish shipowners and the British privateers who took the ship as prize. The proceedings of the court are analysed alongside the political developments between the Spanish and British ministries, and illustrate how they influenced one another. The case demonstrates Hardwicke’s continued attempts to make legal arguments that would set the Rule of the War of 1756 as the standard rule for how Britain’s prize court system would judge the legality of enemy goods carried in neutral ships.

The cases of the Maria Theresa and the America were designed, by Hardwicke, Holderness, and Newcastle, to instil confidence in the Dutch government that the Court of Prize Appeal would safeguard the Dutch neutral rights that had been agreed throughout the first part of the war. They were also designed to instil confidence in British privateers and naval captains and ensure that French colonial trade carried in neutral ships could still largely be stopped and condemned as legal prize. This chapter focuses on the two appellate cases and the legal arguments presented. These are then tied to the legal and strategic maritime thinking of Lord Hardwicke and his creation of the Rule of the War of 1756. This rule became the bedrock for how Britain would understand and negotiate neutral rights over the course of the next major European maritime wars. The basic premise of the rule was that trade that was prohibited to a neutral during times of peace would be considered by the British prize court system to be prohibited in times of war. The chapter, through an analysis of Dutch cases in the Court of Prize Appeal, examines how and why Hardwicke developed this rule.

This chapter provides a contextual overview of the development and operation of the British prize court system. It then introduces the specific legal rules and precedents, specifically the Rule of the War of 1756, that were developed by Britain during the Seven Years’ War in the pursuit of negotiating neutral rights to Britain’s strategic advantage. The chapter critiques the historiography on the Rule of the War of 1756 and makes the argument that the development of the rule and its influence in subsequent wars can only be understood if its strategic drivers are taken into account. The Rule, in other words, was as much a creation of strategic thinking as it was of legal thinking.

The Conclusion delves into the strategic and legal legacies of the Seven Years’ War. It ties the Seven Years’ War and the unresolved tensions around maritime neutrality to the outbreak of Anglo-Dutch and Anglo-Spanish hostilities during the American War of Independence. It does so by examining the peace treaty of 1763 wherein no new significant arrangements were made about neutral rights between the Spanish and the British. The argument is made that the ambiguity of existing treaties left both governments room to continue negotiations whilst the Rule of the War of 1756 would provide an understanding of how British prize courts would treat neutral ships in future conflicts. The chapter examines the legacy of the Court of Prize Appeal and the thinking behind the rule. It discusses how the court and the rule were used in subsequent conflicts through the Napoleonic Wars and the role that individual judges took in making the rule a critical or underplayed element of British maritime strategic thinking. The rule loomed large in British maritime law for many wars after Hardwicke created it and it is, perhaps, one of the best illustrations of the link between law, sea power, and strategic thinking.