sacrifices the indigenous status of the peoples of the Caucasus and Siberia along with the indigeneity of all other Asians. History Classical antiquity Greek sources of the Classical period acknowledge Indigenous people whom they referred to as "Pelasgians". Ancient writers saw these people either as the ancestors of the Greeks, or as an earlier group of people who inhabited Greece before the Greeks. The disposition and precise identity of this former group is elusive, and sources such as Homer, Hesiod and Herodotus give varying, partially mythological accounts. Dionysius of Halicarnassus in his book, Roman Antiquities, gives a synoptic interpretation of the Pelasgians based on the sources available to him then, concluding that Pelasgians were Greek. Greco-Roman society flourished between 330 BCE and 640 CE and undertook successive campaigns of conquest that subsumed more than half of the known world of the time. But because preexisting populations within other parts of Europe at the time of classical antiquity had more in commonculturally speakingwith the Greco-Roman world, the intricacies involved in expansion across the European frontier were not so contentious relative to Indigenous issues. Catholic Church and doctrine of discovery The doctrine of discovery is a legal and religious concept, tied to the Roman Catholic Church, which rationalized and "legalized" colonization and the conquering of Indigenous peoples in the eyes of Christianized Europeans. According to Indigenous rights' activists and legal scholars Robert J. Miller, Jacinta Ruru, Larissa Behrendt, and Tracey Lindberg, the roots of the doctrine go back as far as the fifth-century popes and leaders in the church who had ambitions of forming a global Christian commonwealth. The Crusades (1096-1271), fought to recover the Holy Lands from Muslim conquerors, built on this ambition of a justifiable holy war against those whom the church saw as infidels. Pope Innocent IV's writings from 1240 were particularly influential upon Franciscus de Victoria and Hugo Grotius, secular legalists who lived in the sixteenth and seventeenth centuries and would later contribute significantly to the Doctrine of Discovery in their respective European Kingdoms. Innocent IV argued that Christians were justified in invading and acquiring infidels' lands because it was the church's duty to control the spiritual health of all humans on Earth. The doctrine developed further in the 15th century after the conflict between the Teutonic Knights and Poland over control of "pagan" Lithuania. At the Council of Constance (1414) the Knights argued that their claims were