- Legislature appropriated $50,000 to complete Old Main.
- First graduating class (11 men) received B.S.A. degree (Bachelor of Scientific Agriculture) in December; first to complete baccalaureate program at an American agricultural college.
- School renamed Agricultural College of Pennsylvania, May 1.
- Morrill Land-Grant Act signed by President Lincoln, July 2; established national system of public state universities to "promote the liberal and practical education of the industrial classes in all the pursuits and professions of life;" emphasized agriculture and mechanic arts.
- President Pugh wrote Succinct History of Agricultural Education in Europe and America with account of the Agricultural College of Pennsylvania.
- Graduate program in agricultural chemistry began under President Pugh.
- First master's degree (M.S.A.) awarded in January to C. Alfred Smith, '61.
- Governor Curtin signed Morrill Act Acceptance Act on April 1, designating University as Pennsylvania's land-grant institution; state appointed commission to sell land-scrip, proceeds to form endowment fund from which institution receives income annually; state obligated to provide funds for maintenance; first income received, 1867; first maintenance appropriation from state, 1887.
- William H. Allen became second President; resigned 1866.
- Professor John Fraser appointed third President; planned mechanic arts curriculum and introduced term "practicum;" resigned 1868.
- Three experimental farms purchased under Land-Grant Act in Chester, Indiana and Centre Counties; first two sold in 1887.
- Thomas H. Burrowes named fourth President; died in office, 1871.
- Harvest Home, forerunner of alumni reunions, begun by Burrowes as open house and farmers' implement trials; discontinued 1878.