The University of Oregon (UO) is a public, coeducational research university in Eugene, Oregon, United States. The third-oldest public university in the state (behind Western Oregon University and Oregon State University), the UO was founded in 1876 and graduated its first class two years later. The Carnegie Foundation classifies the University of Oregon as a RU/VH (very high research activity) university, the highest classification for an academic institution. It is one of 108 universities to have such a designation. Additionally, the UO is one of only two Association of American Universities members in the Pacific Northwest.

As the flagship institution of the Oregon University System, the UO is one of the nation's premier public teaching and research universities. The current UO student body is composed of students from all 50 of the United States, the District of Columbia, two U.S. territories, and 89 countries around the world.

The Oregon State Legislature established the university on October 12, 1872, despite the new state's funding woes. The residents of Eugene struggled to help finance the institution, holding numerous fundraising events such as strawberry festivals, church socials, and produce sales. In total they raised $27,500, enough to buy seventeen acres of land. The doors officially opened in 1876, with Deady Hall its sole building. The first year of enrollment contained 155 students taught by five faculty members. The first graduating class was in 1878, graduating five students. In 1881, the university was nearly closed, it was $8,000 in debt before Henry Villard donated $7,000 toward to help pay for the debt. In 1913, and again in 1932, there were proposals to merge the university with what is now referred to as Oregon State University. Evidently, both proposals were defeated.

Oregon (ⁱ/ˈɔrɨɡən/ ORR-ə-gən) is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern boundaries, respectively. The area was inhabited by many indigenous tribes before the arrival of traders, explorers, and settlers who formed an autonomous government in Oregon Country in 1843. The Oregon Territory was created in 1848, and Oregon became the 33rd state on February 14, 1859.

Oregon is the 9th most extensive and the 27th most populous of the 50 United States. Salem is the state's capital and third-most-populous city; Portland is the most populous. Portland is the 29th-largest U.S. city, with a population of 583,776 (2010 US Census) and a metro population of 2,241,841 (2009 estimate), the 23rd-largest U.S. metro area. The valley of the Willamette River in western Oregon is the state's most densely populated area and is home to eight of the ten most populous cities.