To understand this convent, you have to leave Lisbon for a moment and travel to the summer of 1665, to open ground near the Spanish border at a place called Montes Claros. Portugal was in the middle of the Restoration War, the long struggle to defend the independence it had declared in 1640. On the eve of that battle, a Portuguese nobleman made a vow. He was António Luís de Meneses, the first Marquis of Marialva, also known as the Count of Cantanhede. If the Portuguese army won, he promised, he would build a convent dedicated to Saint Peter of Alcântara. The Portuguese did win, and the building you are looking at is the result. One heritage account calls it a monumental ex-voto of the Restoration War, built in 1680 at the Marquis's initiative; another dates the church itself to 1681, so the precise year of each stage is a little blurry in the surviving record. What is clear is the sequence: a promise, a victory, and a Franciscan monastery rising in Bairro Alto before the end of the seventeenth century. Think about what that means. This is not simply architecture. It is a battlefield souvenir in stone, raised to remember a war that kept Portugal Portuguese, and a reminder of how closely religion, politics and military fortune were braided together in this city.