Trans Liberation Beyond Pink and Blue is a hexbear favorite.
Fanon's wretched of the earth is a real strong classic on the "third world"
Anything by web dubois and fred douglass is a good start for the origins of racism in the us. Anything by Dr. King, too.
Blood in my Eye is a good read, and pretty quick.
I will always tell every single human to read The Art of War at least once.