An act of Congress, approved on this day in 1848, solidified the Oregon Territory, an area encompassing present-day Oregon, Idaho, Washington, and parts of western Montana and Wyoming, as an ...

Great Britain sign Oregon Treaty, June 15, 1846 By Andrew Glass 06/15/2012 04:34 AM EDT On this day in 1846, the United States and Great Britain averted waging a potential third war in 70 years by ...