Encountering the people of America raised many questions. The result was a series of pronouncements and diplomatic initiatives from the pope that became known in international law as the doctrine of discovery. By the late 16th century, France and England rejected this as inadequate and demanded a modification, which became the right of conquest. This doctrine became the legal basis for the invasion and occupation of non-Christian America by Christian Europe. ‘The European invasion’ looks at the spread of European exploration, trade, and settlement across America. From the beginning for the Indians of North America, the focus of contention with the Europeans was the land, its resources, and its productive potential.