The Columbia University community and administration mobilized to the fullest extent in answer to the entry of the United States into World War I. Summed up by President Nicholas Murray Butler in the 1918 Annual Report, the effects of the war on the University were far-reaching: "Students by the hundred and prospective students by the thousand entered the military, naval, or civil service of the United States; teachers and administrative officers to the number of nearly four hundred sought and obtained leaves of absence or resigned their posts in order to enter the service of the Government; courses of instruction were modified or abandoned; habitual modes of procedure were altered; the whole University went upon a war footing." Soon after the nation mobilized in 1917, the war effort consumed Columbia in every way, from installation of new courses and military training on South Field to creating a War Records Committee to record every Columbia community member's participation in the war effort. Columbia's mobilization was so intense that the U.S. government used many of Columbia's programs and efforts as an example for the country's other institutions of higher education.

The first direct military activity on campus was on March 8, 1917 when the Columbia Reserve Officers Training Corps (also known as: Columbia Battalion or Columbia Corps) was formed. Within four months of formation, 1400 had enrolled in the Battalion. In April 1918, the Battalion was disbanded when it was announced, that the Reserve Officers Training Corps (ROTC) would be established to replace it. The ROTC, however, was never realized because the U.S. Army created the Student Army Training Corps to fill its place in the summer of 1918.

In April 1917 the Trustees of the University approved the creation of the Columbia War Hospital, a medical training camp, to be located on a piece of land in the Bronx called the Columbia Oval. Due to fear of naval bombardment, the hospital was also meant to handle victims of these bombardments if they occurred or to handle ill soldiers or war disasters. The War Department took over the Hospital on October 3, 1917 and renamed it the U.S. Army General Hospital Number One. In other war efforts, alumni raised enough money in September 1917 to set up the Ambulance Service Division. In addition, the University established the Columbia Service Bureau, part of the American University Union. Horatio S. Krans (CC 1894) headed the Bureau as "a friendly and helpful port of call for hundreds of Columbia soldiers on leave to Paris." (Fon W. Boardman, Jr., Columbia: An American University in Peace and War, p.47).

The University participated in and created many other programs and facilities to further the war effort, including the emergency training corps; establishment of the Military and Naval Bureau in East Hall; Mobilization Committee for Women's Work which organized women for volunteer and salaried positions; the establishment of the United States Navy Gas Engine School; the inclusion of war-related courses being taught through the Department of Extension Teaching; and the creation of the Farm Bureau.