We are now in a position to see clearly some of the factors
involved in the Western problem. For nearly three centuries
the dominant fact in American life has been expansion.
With the settlement of the Pacific coast and the
occupation of the free lands, this movement has come to a
check.... [T]he restless, rushing wave of settlement has
broken with a shock against the arid plains. The free lands
are gone, the continent is crossed, and all this push and
energy is turning into channels of agitation.
-Frederick J. Turner, "The Problem of the West, 1896
OA. The Homestead Act
B. The Gentlemen's Agreement
OC. The Indian Removal Act
OD. The Compromise of 1877