Political map of North America & the Caribbean 14 October 1852 (Opening up the West): The surge in migrants heading west (California Gold Rush) put increasing pressure on the Oregon Trail. To secure the Trail, the US government signed the Treaty of Fort Laramie (Treaty of Fort Laramie (1851)) with the tribes of the Great Plains, who agreed to guarantee the safe passage of travelers and allow for the construction of forts in return for an annuity. Promised for fifty years, the Treaty barely lasted five before settlers and prospectors were spilling off the Trail in search of land and gold (Pike's Peak Gold Rush).