Final answer:
The main goal of the government in negotiating treaties with First Nations was to secure land for expansion and establish the security of the nascent United States. The methods of treaty negotiation often involved pressure and the treaties were not always honored, leading to dependency of tribes on the government and loss of autonomy for First Nations.
Step-by-step explanation:
The primary goal of the government in negotiating treaties with First Nations was to acquire land and ensure the security of the United States by allying with Indian groups to prevent foreign encroachment. The negotiation of these treaties was often fraught with pressure and unfair practices, including the signing of treaties under duress or with individuals who lacked authority. These treaties generally comprised land cessions by various tribes in exchange for compensation in the form of services, reservations, rights, and monies, although the U.S. government notoriously failed to honor many of these agreements.
As the nation expanded, treaties were also seen as a means to promote a policy of 'civilizing' native populations, with the expectation that they would adopt farming and settle down, thus facilitating assimilation into the expanding American society. The treaties had varying impacts on the indigenous population, often resulting in their dependency on the federal government due to the provisions for annual stipends of basic provisions instead of cash payments. As immigration increased, these treaties were frequently disregarded, leading to further loss of land and autonomy for First Nations, culminating in the Indian Act of 1876 which imposed even greater controls over Indigenous Peoples.