In common with most of its neighbors, the foreign policy of Peru after independence in 1821 focused on core interests that can be summarized as political sovereignty, territorial integrity, continental solidarity, and economic independence. Over the next 200 years, Peruvian foreign policy expanded in scope and direction; nevertheless, these four tenets continued to encapsulate the nation's external policy. Consequently, the permanent interests of Peru remain a logical place to begin an assessment of Peruvian foreign policy in the modern era.

Political Sovereignty

In the early years of independence, Peru struggled to decide whether it would divide, federate with Bolivia, or stand alone. Like most newly independent states, Peru achieved statehood long before it achieved nationhood, and it sometimes struggled to retain the former as it strived to develop the latter. From the outset, the Peruvian Diplomat Service played a decisive role in the legal defense of the national inheritance often in vast, encyclopedic defenses of Peruvian territorial claims. Over time, Peru faced nine wars (two with Chile, two with Colombia, two with Ecuador, and three with Bolivia). After each one, Peruvian diplomats negotiated a peace mostly on terms favorable to Peru. Having achieved political sovereignty in the nineteenth century, there was little serious challenge to it, apart from a few territorial issues, in the twentieth century.

The issue of political sovereignty surfaced again during the Castillo administration. In late 2021, former Bolivian president Evo Morales announced his intention to hold a meeting in Cuzco of RUNASUR, an organization that entertained vague plans of constructing a plurinational nation from Bolivia, Ecuador, and Peru. In response to efforts to organize the Cuzco gathering, the Foreign Relations Committee of the Peruvian congress condemned what it termed the political activism of Morales and called for President Castillo to declare Morales persona non grata. A few days later, three former foreign ministers and eight former vice foreign ministers issued a joint statement denouncing the proposed RUNASUR forum as a clear threat to the national sovereignty, independence, and security of Peru. The Cuzco forum was later postponed; nevertheless, the declared objectives of RUNASUR remained a latent threat to the political sovereignty of Peru. The RUNASUR issue surfaced again during the demonstrations that swept Peru in 2022–23.