Final answer:
White settlers initially left Native Americans alone on the Great Plains due to treaties and logistical challenges. However, driven by economic interests and the ideology of Manifest Destiny, this attitude changed, leading to forced relocations and increased conflicts as whites sought to appropriate native lands for resources.
Step-by-step explanation:
The Great Plains were initially left undisturbed by white settlers due to a combination of factors including treaty agreements, the desire for peaceful coexistence, and the logistics of settling the harsh plains environment. However, as the 1850s approached, several factors spurred an attitude change leading to increased conflict and displacement of Native Americans.
Economic interests, driven by a desire for land for farming, mining, and cattle ranching, led settlers to desire land previously solely used by Native Americans. The discovery of gold and other valuable resources further intensified this interest, generating conflicts over land rights.
The concept of Manifest Destiny also played a key role, as it was the belief that Americans had a divine right to expand across the continent, which included appropriating lands inhabited by Native American tribes. This ideology justified many of the subsequent actions taken against Native populations.