Simplify the following text for a Grade 7 native English-speaking person.
Original: On August 14 , 1848 , Congress passed the Act to Establish the Territorial Government of Oregon , which created what was officially the Territory of Oregon .
Simplified: The Territory of Oregon was organized on August 14 , 1848 , by an act of Congress out of the U.S. portion of the Oregon Country below the 49th parallel north .