Fading support for reconstruction was preceded by

Public support for Reconstruction policies, requiring continued supervision of the South, faded in the North after the Democrats, who strongly opposed Reconstruction, regained control of the House of Representatives in 1874. The Reconstruction era ended in 1877 with no great advances.

indigenous people north and south were displaced, died of disease, and were killed by europeans through slavery, rxpe, and war. in 1491, about 145 million people lived in the western hemisphere. by 1691, the population of indigenous americans had declined by 90-95 percent, or by around 130 million people."

while it was true that the cotton gin reduced the labor of removing seeds, it did not reduce the need for slaves to grow and pick the cotton.

explanation:

before eli whitney's invention of the cotton gin, picking and cleaning cotton was a slow, labor-intensive job. workers, usually slaves, had to pick the seeds from the cotton fibers by hand. this invention made it possible to grow large amounts of cotton on big farms and make money.