In 1843 Congress was considering a bill that would allow every adult male settler in the Pacific Northwest to claim 640 acres of land. He could also claim 160 for each child and 160 for his wife. That spring, with the promise of these land grants, more than one thousand pioneers left Independence, Missouri, on the 2,000-mile trail to Oregon. By 1846 many thousands of pioneers were moving west.

Most pioneers began their journey at one of the jumpingoff towns along the Missouri River. The trail followed the Platte River in Nebraska to Fort Laramie in Wyoming and across the mountains of the Continental Divide at South Pass. In the southwest corner of Wyoming, the wagon trains could stop to buy supplies and rest at Fort Bridger. This was actually a trading post built by the trapper Jim Bridger, who charged travelers very high prices at this frontier convenience store.

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