In Chapter 5 of A People's History of the United States, what happens to the Indians whose land is taken over by America's expansion, and the black slaves? And what does this have to do with the thesis of the chapter?
The major thesis of this chapter is that the American Revolution was fought mainly by the poorer and common people and was overseen by the elites. The elites ensured that the Revolution would be fought for their own interests, not for the interests of the lower classes. The connection between this thesis and the Indians and the African American slaves was that these were the lowest of the lower classes. The Revolution was by no means fought for their interests.
In the aftermath of the Revolution, the Native Americans suffered. They had generally sided with the British because they knew that the colonists, if independent, would be more aggressive about trying to take their land. After the war, the Americans did try to take the Indian lands but were not always successful. However, they did certainly exclude Indians from their new society.
The same thing happened to the slaves. The slaves were not seen as true members of the society. They could be used, at times, to fight in the Revolution, but they could not be given any of the benefits of winning the war. Therefore, they were not really included as citizens of the new country either.
Generally, then, what happened to Indians and slaves is that they were excluded from society (or at least from an equal place in it). This shows that the American elites were acting in their own interests, not in the interests of any other groups.