1400s - Discovery doctrine

         The origins of the Discovery Doctrine can be traced back to the Crusading-era papacy of Innocent III and IV, in the thirteenth century (see Innocent III in Faces).  Two centuries later, Pope Nicholas V gave a Portuguese king permission to claim lands his armies had 'discovered in Africa.  Pope Alexander extended those same territorial imperatives to Spain's King Ferdinand and Queen Isabella in 1493, granting them the right to conquer lands and peoples in the new world across the sea.  Arguments between Portugal and Spain led to a treaty which clarified that only non-Christian lands could thus be taken, as well as drawing a line of demarcation to allocate potential discoveries between the two powers.

            Though its origins were theocratic in nature, the Discovery Doctrine became a settled concept of international law in the 16th and 17th centuries. At that time, European monarchs claimed primacy over lands owned by native people, but European governments began disavowing this doctrine in the 18th century.  The United States, however, incorporated the legal tenets of the Discovery Doctrine into its founding principles.  Chief Justice John Marshall gave conditional support to those tenets in his opinion in Johnson v McIntosh, in 1823.    Nevertheless, ten years later, in Worcester v. Georgia,  he also ruled that Indian nations were sovereign governmental entities retaining all of the privileges accorded to nationhood.

click here for more on the discovery doctrine