 As has been indicated, the School of Salamanca is credited with a role in the development of international law. The gradual detachment of the ius gentium from natural law, particularly as it pertained to issues such as slavery and the slave trade, was another notable accomplishment, So, too, was its consistent defense of the full humanity of the Amerindians. That argument could be applied to other non-European peoples who had also never heard of Jesus; their regimes and property rights were closely tied to reason and natural law.