http://scholarship.law.nd.edu/cgi/viewcontent.cgi?article=1888&context=law_faculty_scholarship
"A systematic theoretical foundation for both international law and universal human rights emerged in Catholic thought at least as early as the sixteenth century in the work of Francisco de Vitoria and his contemporaries in Salamanca, Spain. The classical natural law account characteristic of the Catholic intellectual tradition has consistently understood the paradigmatic definition of law to be tied to the good of the human person through law’s proper orientation to the common good. Out of his deep reflections on the Spanish encounter with the peoples of the New World, Vitoria expanded the Thomistic notion of the common good to incorporate into it the ius gentium, the law of nations. Vitoria analogized the whole world to a single commonwealth, in which all of the human family shares in a single common good. Synthesizing the juridical concepts of rights drawn from the canon law with the philosophical tradition of natural law, Vitoria and his followers also vigorously and systematically defended the rights of the American Indians to ownership of their lands, to equality, and to sovereignty, principally on the basis that the natural rights of the Indians were grounded in their creation as rational beings in God’s image. The School of Salamanca thus represents an early and lucid example of Catholic human rights discourse."
-Carozza, Paolo G. and Philpott, Daniel, "The Catholic Church, Human Rights, and Democracy: Convergence and Conflict with the
Modern State" (2012). Scholarly Works. Paper 882, p.17-18.
"A systematic theoretical foundation for both international law and universal human rights emerged in Catholic thought at least as early as the sixteenth century in the work of Francisco de Vitoria and his contemporaries in Salamanca, Spain. The classical natural law account characteristic of the Catholic intellectual tradition has consistently understood the paradigmatic definition of law to be tied to the good of the human person through law’s proper orientation to the common good. Out of his deep reflections on the Spanish encounter with the peoples of the New World, Vitoria expanded the Thomistic notion of the common good to incorporate into it the ius gentium, the law of nations. Vitoria analogized the whole world to a single commonwealth, in which all of the human family shares in a single common good. Synthesizing the juridical concepts of rights drawn from the canon law with the philosophical tradition of natural law, Vitoria and his followers also vigorously and systematically defended the rights of the American Indians to ownership of their lands, to equality, and to sovereignty, principally on the basis that the natural rights of the Indians were grounded in their creation as rational beings in God’s image. The School of Salamanca thus represents an early and lucid example of Catholic human rights discourse."
-Carozza, Paolo G. and Philpott, Daniel, "The Catholic Church, Human Rights, and Democracy: Convergence and Conflict with the
Modern State" (2012). Scholarly Works. Paper 882, p.17-18.