Interesting Legal History

The Iroquois Confederacy has been staging a number of events to raise awareness of environmental conservation and land rights as they haven't gotten anywhere in the courts:

In 2005, the Onondaga filed a lawsuit against New York State, the city of Syracuse, Onondaga County, and five corporations, claiming that the state had illegally seized the tribe's land and that the corporations had been destroying the environment in the area. At the time, The New York Times reported that the tribe was using the land claim as leverage to force environmental cleanup--they had no intention of taking back the land by evicting people currently living on it. Rather, one of the key issues was that the company Honeywell International, among others, had for decades been dumping chemical waste into Onondaga Lake, a sacred site. The lake, an EPA superfund site, is now one of the most polluted in the country, and has a thick layer of mercury at its bottom.
The courts have categorically dismissed the cases and subsequent appeals. Part of the problem with the land rights struggle is the Doctrine of Discovery, which states that European explorers and settlers have superior rights to the land. This doctrine flows from a decree by Pope Nicholas in 1452 to allow the subjugation of "heathen" lands in Africa and the New World. It was adopted by American law in 1823 in the Supreme Court case Johnson vs. McIntosh, and never overturned. Recently, it was used in 2005 as part of a court decision to dismiss an Oneida land case.

I never quite knew how the courts justified land grabs by the government from Native Americans.  Here's more on the Doctrine of Discovery:

 The origins of the doctrine can be traced to Pope Nicholas V's issuance of the papal bull Romanus Pontifex in 1455. The bull allowed Portugal to claim and conquer lands in West Africa. Pope Alexander VI extended to Spain the right to conquer newly-found lands in 1493, with the papal bull Inter caetera, after Christopher Columbus had already begun doing so. Arguments between Portugal and Spain led to the Treaty of Tordesillas 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.
According to the United States Supreme Court's decision in Johnson v. M'Intosh, this theory of Christian expansion and possession of newly discovered lands, despite native presence, was one by which all colonial powers operated. Chief Justice Marshall, writing the decision, held that the United Kingdom had taken title to the lands which constituted the United States when the British discovered them. Marshall pointed to the exploration charters given to John Cabot as proof that the British had operated under the doctrine.  The tribes which occupied the land were, at the moment of discovery, no longer completely sovereign and had no property rights but rather merely held a right of occupancy. Further, only the discovering nation or its successor could take possession of the land from the natives by conquest or purchase. Natives could not sell the land to private citizens but only to the discovering government.

The doctrine was used in numerous other cases as well. With Cherokee Nation v. Georgia, it supported the concept that tribes were not independent states but "domestic dependent nations". The decisions in Oliphant v. Suquamish Indian Tribe and Duro v. Reina used the doctrine to prohibit tribes from criminally prosecuting first non-Indians, then Indians who weren't a member of the prosecuting tribe.

It is interesting that the Court has come under attack for referencing international law as precedent in recent years, when the basis for our claim of all the land we own is staked to a papal bull issued in 1455.