It all relates to the American demands for acquiring all the territory in Oregon from Britain. Manifest destiny is what best describes the idea of the US desire to expand to the pacific region. The victory of Polk in 1844 was a mandate for Manifest Destiny and led to the annexation of Texas. In the dispute with Britain over Oregon, the US demanded continuously for control over the whole territory as far north as "fifty-four forty. The end result of the conflict between the US and Britain over Oregon was a compromise agreement on a border at the forty-ninth parallel.
