The University of the Philippines Diliman (commonly referred to as UP Diliman, or informally, Peyups), is a coeducational and public research university located in Quezon City, Philippines. It is the flagship campus, seat of administration, and the fourth oldest constituent university of the University of the Philippines System, the national university of the Philippines.
Delegated in 1939 as the new campus of then University of the Philippines centered in Manila, the Diliman campus was created from the 493-hectare area of the Diliman district of the then newly established Quezon City to address the increasing population of the university and to acknowledge the demands to expand its roster of academic programs. The outbreak of World War II hampered the development of the area.
Under the governance of UP President Bienvenido Gonzalez through a P13 million grant from the US-Philippines War Damage Commission, much of the UP was transferred from its campus in Manila to the bigger Diliman campus and delegated UP Diliman as the University of the Philippines System's seat of administration. The transfer of the Oblation from Manila to Diliman marked the campus's establishment on February 12, 1949.
Between the 1970s and 1980s, UP Diliman was the site of much student activism. It was during these times that student demonstration and opposition against Marcos' administration became heavy and aggressive. This was one of the precursors to Marcos' declaration of martial law in 1972.
UP Diliman was formally established as a constituent university on April 23, 1985 at the 976th Meeting of the U.P. Board of Regents.