Francisco de Vitoria (Francisci de Victoria; c. 1492 – 12 August, 1546) was a Spanish Renaissance Roman Catholic philosopher and theologian, founder of the tradition in philosophy known as the School of Salamanca, noted especially for his contributions to the theory of just war and international law. He is considered the "father of international law".
A noted scholar, he was publicly consulted by Charles V, Holy Roman Emperor and King of Spain. An important part of his influence was the justification of the imposition of Spanish imperial power over the indigenous inhabitants of America, although he was not as thoroughgoing in these justifications as the emperor might have liked. His works are known only from his lecture notes, he himself having published nothing in his lifetime, nevertheless his influence, such as on the Dutch legal philosopher, Hugo Grotius, was significant; Relectiones XII Theologicae in duo libros distinctae was published posthumously (Antwerp, 1604).
Notes of his lectures from 1527-1540 were copied by students and published under the following titles: