Domestic politics and the escalation of commercial rivalry : Explaining the War of Jenkins ’ Ear , 1739 – 48

The study of international rivalry is a thriving research program in international relations, but it focuses primarily on strategic rivalries and generally neglects both commercial rivalries and the impact of domestic politics. We examine commercial rivalry and the causal paths through which it can escalate to war. After identifying alternative theoretical explanations, we focus on the Anglo-Spanish rivalry of the 1730s and the processes through which it escalated to the War of Jenkins’ Ear (1739–48). We examine both balance of power and dyadic trade rivalry explanations, and then give special attention to domestic politics in Britain. We argue that the commercial rivalry was a necessary but not sufficient condition for the war of 1739. The Walpole ministry was opposed to war, and the rivalry would not have escalated in the absence of domestic pressures from mercantile interests, a xenophobic public, a politically opportunistic parliamentary opposition, and a divided cabinet.