Which event had the biggest impact on the lives of native Americans in the mid 1800's? The end of the civil war? The California gold rush? The Spanish American war? The invention of the steamboat?

The Gold Rush Impact on Native Tribes ... The gold rush of 1848 brought still more devastation. Violence, disease and loss overwhelmed the tribes. By 1870, an estimated 30,000 native people remained in the state of California, most on reservations without access to their homelands.