Modern States Formed from the Oregon Territory: Oregon, Washington, Idaho, Wyoming, Montana

The Oregon Territory (organized August 14, 1848 – admitted as state February 14, 1859) encompassed the Pacific Northwest. Present-day states fully or partially carved from it include:

• Oregon
• Washington
• Idaho
• Wyoming
• Western Montana

The territory's boundaries were defined by the 49th parallel north (U.S.–Canada border) and the Continental Divide.