Os Lusíadas (The Lusiads) is the national epic of Portugal. Written by the poet, soldier, and sailor Luís de Camões (circa 1524–80) and first published in 1572, it celebrates the great Portuguese explorer Vasco da Gama (1469–1524) and the achievements of Portugal (known during the Roman Empire as the province of Lusitania, hence the title) and its people in venturing out into the Atlantic, rounding the tip of Africa, and forging a path to the East Indies. Manuel de Faria e Sousa (1590–1649) was a Portuguese historian and poet who spent much of his life in Madrid. Faria e Sousa wrote, in Spanish, a long commentary on Os Lusíadas, most of which was published after his death. Presented here is a 19th-century translation into Portuguese, in manuscript, of Faria e Sousa’s commentary. The translation is by Manuel Nunes Godinho (circa 1816–82); the calligraphy by Domingos Nunes Godinho. The manuscript is from the library of the Brazilian-Portuguese scholar, collector, and bibliophile Antonio Augusto Carvalho Monteiro (1848–1920), which was purchased by the Library of Congress after his death.