School of Salamanca
Sixteenth-century movement of theologian-jurists at the University of Salamanca, founded by Francisco de Vitoria, that laid groundwork for modern international law — separating the law of nations from natural law and defending the property rights of non-Christian peoples — and for monetary economics, including the first formulation of the quantity theory of money.
Why this wins its question: Standard histories of international law start with Grotius and of economics with the English classics. This object binds the earlier Salamancan record to the current Stanford Encyclopedia entry (verified) and the foundational monograph, claim by claim — priority claims stated precisely enough to survive checking.
Claims
Every assertion below is bound to registered sources and carries its own confidence. Weight them; do not treat the page as uniformly authoritative.
Francisco de Vitoria (1486-1546), teaching at Salamanca from 1524, was the founding figure of the school; in his relectiones on the Indies he argued that the native peoples of the Americas held legitimate dominion and property rights despite not being Christians, and set out criteria distinguishing just from unjust war.
Vitoria and his colleagues separated the ius gentium (law of nations) from natural law, with which it had been more or less identified since Roman law — a conceptual move foundational for international law as a discipline.
Martín de Azpilcueta produced the first formulation of the quantity theory of money, attributing Spanish inflation to the large-scale importation of American specie, and Luis de Molina grounded just price in market estimation rather than production cost.
Economic historiography since Grice-Hutchinson (1952) treats the Salamanca theologians of 1544-1605 as early monetary theorists whose analysis anticipated results usually credited to later northern European writers.