Thinking about the Native Americans, and the devastation they suffered, has there ever been an attempt to allow them to form their own country, giving them any part of the USA's land?
Would their connection to the land (history, culture, religion, etc.) and the devastation they suffered have any value in trying to form an independent country within the USA's land using U.S. laws?
Yes, but not a fully independent country.
By the end of the 18th century, after the US War of Independence, Europeans began to expand further west and this brought renewed conflict between indigenous people (ie "Indians") and Europeans.
A plan was hatched to remove all indigenous nations to a region west of the Mississippi, that would become known as "Indian Country" or "Indian Territory". Eventually, the Indian country or the Indian Territory would encompass the present states of Oklahoma, Kansas, Nebraska, and part of Iowa. This process began in around 1800, but was formalised and extended under President Jackson in 1825. However although called "Indian territory" it was not formally a territory as defined by law and the Constitution.
This region would be owned by the USA but independent of the States. Many people living East of the Mississippi were "ethnically cleansed" to the West, in a process that included the "Trail of Tears".
Although the intent in 1825 had been to resolve the "Indian question" by the creation of a country for indigenous nations, the federal government retained overall control of the region, as European immigration continued into the interior of the continent, Federal USA took back political power. Indian country was progressively reduced, packaged, and converted into States, with European majorities and European governments, with the indigenous people being further forced to the less valuable lands in reservations.
Now, I get that you are seeking to draw an analogy between the Jewish people in Israel and the indigenous American nations. However remember that the region occupied by these nations includes all of the current United States (except Hawaii), Canada and Mexico. Populations were densest roughly where they are dense now. There isn't a compact region to which to return; there's no Palestine. And there are some powerful vested interests that would strongly oppose ceding the land in New York (for example) to the descendants of its original inhabitants (even assuming they could be traced).
The approximately 325 federal Indian reservations are formally and legally called "domestic dependent nations". So, you might consider this "their own countries".
As domestic dependent nations, Indian tribes exercise inherent sovereign powers over their members and territory.
The United States recognizes the right of Indian tribes to self-government and supports tribal sovereignty and self-determination.
NCSL (2013):
The U.S. Constitution recognizes Indian tribes as distinct governments and they have, with a few exceptions, the same powers as federal and state governments to regulate their internal affairs.
Tribes possess all the powers of self-government, including the rights to:
• Form a government
• Make and enforce laws, both civil and criminal
• Tax property or sales
• Establish and determine tribal membership
• License and regulate activities within their jurisdiction (including hunting, environmental control, land use, and gambling)
• Exclude people from tribal lands
Tribes cannot declare war, engage in foreign diplomacy, or print and issue their own currency.
Britain proposed an independent state, barrier state, or buffer state for Native Americans several times both before and after the American Revolution. While you might say that this answer is not applicable to a question tagged [united-states], some historians believe that the British laws reserving lands for Native Americans were a cause of the American Revolution, and formed the background some of the causes of the American Declaration of Independence.
Britain proposed a state for Native Americans during the French and Indian War (1754-1763), after its victory over France in 1763 in the leadup to the American Revolution, and after American independence up to the Treaty of Ghent (1814) that concluded the War of 1812.
I'll let a number of wikipedia articles speak for themselves, with excerpts as of the time I post this in case they are subsequently changed.
In particular Indian barrier state, Royal Proclamation of 1763, Indian Reserve (1763).
By the way, these wikipedia articles exhibit an interesting mix of attitudes. Some parts are pro-British, some pro-American, some pro-First Nations, stating as fact what is often opinion. Usually, of course, the properly footnoted opinion of a historian -- but on a topic like this nationalistic historians often slant things. The objectivity of these articles is not quite as bad as those of, say, the history of Ukraine and Russia dating back to Kievan Rus, or of discussions about whether the American Revolution may or may not have been fought to protect slavery from reform. Nevertheless interesting.
Wikipedia article Indian barrier state:
The Indian barrier state was a British proposal to establish a Native American buffer state in the portion of the Great Lakes region of North America. It was never created. The idea was to create it west of the Appalachian Mountains, bounded by the Ohio and Mississippi rivers and the Great Lakes.
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Among the plan's most ardent proponents were Mohawk leader Joseph Brant and Lieutenant Governor of Upper Canada John Graves Simcoe.3 In 1814 the British government abandoned efforts to bring such a state into being with the signing of the Treaty of Ghent with the United States.
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The British first proposed a barrier state in discussions with France in 1755. In 1763, Britain took control of all of the land east of the Mississippi River, and so negotiations with France became irrelevant.
In 1763, following the French and Indian War (the North American component of the Seven Years War), Britain gained control French Quebec, and the territory between the British colonies in North America and the Mississippi, west of the Appalachians and east of the Mississippi.
King George III's Royal Proclamation of 1763 forbade all European settlements west of the Appalachians, establishing the (British) Indian Reserve (1763).
Excerpting wikipedia page Indian Reserve (1763)
The Royal Proclamation of 1763 organized on paper much of the new territorial gains in three colonies in North America—East Florida, West Florida, and Quebec. The rest of the expanded British territory was left to Native Americans.
Excerpting Royal Proclamation of 1763
The lands west of Quebec and west of a line running along the crest of the Allegheny Mountains became (British) Indian Territory, barred to settlement from colonies east of the line.
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All land with rivers that flowed into the Atlantic was designated for the colonial entities, while all the land with rivers that flowed into the Mississippi was reserved for the Native American populations. The proclamation outlawed the private purchase of Native American land, which had often created problems in the past. Instead, all future land purchases were to be made by Crown officials "at some public Meeting or Assembly of the said Indians". British colonials were forbidden to settle on native lands, and colonial officials were forbidden to grant ground or lands without royal approval. Organized land companies asked for land grants, but were denied by King George III.
Returning to Indian barrier state:
Through the Quebec Act of 1774, the British made the western lands part of Quebec. That is, they were to be under the control of the British governors based in Quebec. This was one of the Intolerable Acts that eventually led to the American Revolution.
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At the Paris treaty negotiations of 1782, the French floated a proposal that would give the British control north of the Ohio River, with the lands south of the Ohio River and east of the Mississippi River divided into two Indian states. The state to the southeast would be under American supervision; the state to the southwest would be under Spanish supervision. The Americans rejected the plan. The final Treaty of Paris gave the western lands to the United States...
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In the early 1790s, British officials in Canada made an aggressive effort to organize the various tribes into a sort of confederation that would form the basis of an Indian state.
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The War of 1812 in the west was fought for control of the would-be barrier state. ... The American negotiators at Ghent in 1814 refused to entertain proposals for a buffer state; they insisted on abiding by the terms of the Paris Peace Treaty and the Jay Treaty, which assigned the United States full control over Michigan, Wisconsin, and points south. Henry Goulburn, a British negotiator who took part in the Treaty of Ghent negotiations, remarked after meeting with American negotiators that "I had, till I came here, had no idea of the fixed determination which prevails in the breast of every American to extirpate the Indians and appropriate their territory."
At last in August 1814, peace discussions began in neutral Ghent. As the peace talks opened, American diplomats decided not to present President Madison's demands for the end of impressment and his suggestion for Britain to turn Canada over to the United States.[9] They were quiet, and so the British instead opened with their demands, the most important of which was the creation of an Indian barrier state in the former Canadian southwest territory (the area from Ohio to Wisconsin).[10] It was understood that the British would sponsor the Indian state. For decades, the British strategy had been to create a buffer state to block American expansion. The Americans refused to consider a buffer state or to include Natives directly in the treaty in any fashion. Henry Goulburn, a British negotiator who took part in the treaty negotiations, remarked after meeting with American negotiators that "I had, till I came here, had no idea of the fixed determination which prevails in the breast of every American to extirpate the Indians and appropriate their territory."[11] Adams argued that there was no precedent for including Native allies in Euro-American peace treaties and to do so would in effect mean the United States was abandoning its sovereign claims over Native homelands, especially under a foreign protectorate like Britain. In doing so, Adams articulated a strong imperial claim of sovereignty over all peoples living within the boundaries of the United States. The British negotiators presented the barrier state as a sine qua non for peace, and the impasse brought negotiations to the brink of breakdown. In the end, the British government backed down and accepted Article IX, in which both governments promised to make peace with their indigenous foes and to restore Native peoples to "all possessions, rights and privileges which they may have enjoyed, or been entitled to in 1811."
It's an interesting question but it doesn't take into consideration the fact that many of these tribes were mortal enemies and had been raiding, attacking, and killing each other for who knows how long. Many put their differences aside, at times, to work together in fighting the European Westward expansion. However, I don't think lumping all the various tribes into a single country would have ever worked. If it was possible don't you think that would have been done when they created the Reservation system in the first place?
No one has mentioned the proposed Amerindian state of Sequoyah.
It would have been a federation of different tribal groups, mainly those from the SE US that were (often forcefully) relocated there.
