The organization of the Oregon Territory was formalized through an act passed by Congress, primarily aimed at regulating settlement and governance in a region experiencing rapid influxes of settlers due to the westward expansion in the United States. As thousands of emigrants traveled the Oregon Trail seeking new opportunities, the need for a structured governance model became increasingly urgent. The act defined the boundaries of the territory and established a framework for its administrative and governmental operations. In doing so, it provided for a territorial government led by a governor, a legislative assembly, and a judiciary, which collectively ensured legal order as Americans settled the region.

The territory was bound by the Columbia River on the north and the California border on the south, covering parts of what are now the states of Oregon, Washington, and Idaho. Developments leading up to the act were rooted in earlier treaties and explorations, such as the Lewis and Clark Expedition, which had mapped much of the area. Additionally, the Oregon Donation Land Act, passed in 1850, aimed to encourage settlement by granting land to married couples, further promoting the population growth of the territory alongside the governance structure established by Congress.

This organizational act had far-reaching implications. It set a precedent for future territorial governance in the United States and reflected the nation's growing ambition towards westward expansion. As settlers moved into Oregon Territory, they brought diverse cultures, ideas, and practices, all contributing to the unique character of the region. Additionally, the governance model established laid down the legal framework which would ultimately assist with the transition of Oregon from a territory to a state, fostering an environment of growth and development in the years to come.