Marshal Andrés de Santa Cruz was a leader in the triumphant Bolivarian army, the president of Peru from 1826 to 1827, the dynamic successor to General José de Sucre as Bolivian president in 1829, and Supreme Protector of the Peru-Bolivian Confederation between 1836 and 1839. Born in La Paz, he was the son of a creole military offcer and an indigenous noblewoman descended from the mallkus of Lake Titicaca. Considered “white” in most elite circles, he was nonetheless scorned by his opponents for his “Indian” ancestry, particularly in the viceregal capital Lima. Dissatisfied with the debilitating national boundaries defined at independence, Santa Cruz believed that Bolivia needed to be united with Peru, as it had been earlier in the colonial period. Taking advantage of political divisions in Peru in the 1830s, he set about creating his grand territorial confederation through alliances with Peruvian forces, especially in the south. Though recognized by the United States, Britain, and France, all of whom sought commercial entrée in the region, the confederation provoked intense hostility, both within Peru and Bolivia and from their neighbors, and was short-lived. In light of Bolivia’s later political, economic, and territorial weaknesses and marginalization, it is remarkable to see the willingness of Peruvian regions such as Arequipa, Ayacucho, Cuzco, and Puno to join forces with Bolivia in this era. The two documents presented here, from 1836 and 1837, reflect southern Peru’s participation in the alliance under the authority of Santa Cruz and announce the full consolidation of the confederate pact.