This painting shows "Manifest Destiny" , which is the idea that the United States should grow from the Atlantic Ocean to the Pacific Ocean (from Shining Sea to Shining Sea).

In 1872 artist John Gast painted this romanticised scene of people moving west. Called "Spirit of the Frontier", it showed settlers moving west, guided and protected by Columbia (who represents America and is dressed in a Roman toga to represent classical republicanism) and helped by technology (railways, telegraph), driving American Indians and bison (buffalo) away from the land that the Europeans had claimed, and finally to death. Columbia is bringing the "light", that is "civilisation", as people knew it, from the eastern side of the painting as she travels above the settlers towards the "darkened" "uncivilised" west.

This picture also brings many historical events together in a way which did not happen in reality. The Oregon Trail, for example, was opened up decades before the railway. The harsh displacement of American Indians is not considered at all. The killing of bison was to deprive American Indians of food so they would move away or starve, and make the land easier for European Americans to settle on. It was driven by the desire of the railway owners to make money.