tl,dr: Despite facing protracted genocide, Native Americans have always and continue to have an impact on U.S. politics.

In this post I'll just sketch out really broad contours of U.S. Indian policy post-removal; hopefully it'll give you a grounding in how the U.S. has treated Native nations and how they've responded. Please know this isn't comprehensive.

Post-removal to Civil War: Removal took place during the 1830s. This was followed by considerable tumult as tribes removed to "Indian Territory" attempted to reestablish political structures and reckon with the profound effects of forced migration. During the Civil War, the Five "Civilized" Tribes (Cherokee, Chickasaw, Choctaw, Seminole, and Creek) fight on both sides. Each of these tribes practiced slavery to some degree (in fact, this was part of why they were considered "civilized"), but they also considered how who they aligned with during the Civil War may impact their tribe's sovereignty. During the Civil War, the government is simultaneously waging war on Native nations. Events like the horrific Sand Creek Massacre took place during this time. They foreshadowed, in some ways, the genocidal policies of the post-Civil War U.S.

Post Civil War to IRA: After the Civil War was, in my view, the most large-scale manifestation of genocide against Native people. U.S. politicians, businessmen, and the public united around Westward expansion, and deployed a number of tactics to make that possible (that is, to eliminate the Native nations who were already there). The military waged direct wars on Native nations all over the West, often engaging in massacres. The Dawes Act (and subsequent strengthening legislation) privatized Native land which had previously been collectively owned. Families would receive an 'allotment' of common tribal land in proportion to their size to farm. Native nations no longer had land to call their own, with borders and a political organization; Native people had private property, and were expected to follow the laws of the United States. Not coincidentally, the allotment line-drawing process left many plots as "surplus", which were sold to white settlers.

This land-based political/economic devastation was supplemented by cultural genocide in the form of Indian Boarding Schools, where children were sent (usually by coercion of the U.S. government) to be "civilized". School usually practiced strict military-style discipline and expressly forbid students from speaking their first languages or otherwise maintaining their cultural practices. A tremendous number of students experienced assimilationist education. The Bureau of Indian Affairs (BIA) also promoted assimilation, usually with the help of U.S. troops. The Ghost Dance ban and subsequent Wounded Knee Massacre are good examples of this.

Land dispossession, fracturing of political structures, direct violence, and cultural genocide continued through the 1930s. What's important to understand is that Native people, despite experiencing these repressive policies, found ways to keep their cultural practices alive. They danced in secret, and killed U.S. troops right back. Certain leaders courted favor with the BIA and used it to secure land for tribal members. And Native people also found opportunity to subvert government expectations. For example, the now-popular jingle-dress dance, popularized in the late 1910s, was a way of skirting BIA bans on dancing; Native tribes claimed it was a patriotic celebration of WWI veterans, rather than a showing of cultural survivance. Further, the boarding schools created a generation of Native people with a deeper pan-Indigenous conscious than ever before, who would go on to be the fiercest advocates for the political rights of Native people during the Roosevelt administration, when the next chapter of U.S. Indian policy began under the Indian Reorganization Act (IRA).

[check back tomorrow for IRA to present; don't have time to finish right now]