Which former slave became an adviser to the president and spoke out on behalf of poor people—white and black—and for the rights of women, chinese immigrants, and native americans?

The answer is Frederick Douglas.  He was born a slave but later learned to read and write. He escaped slavery and joined the Abolitionist Movement to preach against the system of slavery.  He later became a writer and newspaper editor.  He was an adviser to President Lincoln.  Douglas is proof that slaves had intelligence and talent that slave owners put down.

b. they tried to evict the squatters from the area.

so sorry if wrong