Answer:
Native Americans on the Great Plains
Step-by-step explanation:
Many people who moved from the east onto the plains would erect permanent settlements and farms, whereas Native Americans on the Great Plains were roaming tribes that moved their camps often. As settlers advanced into the Great Plains both settlers and soldiers forced Native Americans to assimilate into white culture and lose their cultural traditions and identity. In layman terms, Horace Greeley is disregarding the interests of Native Americans on the Great Plains because they'd often be forced out of their home to make way for settlers or pressured to assimilate and abandon their culture.