The republican militias' objective was the defense of the capital at all costs, and for that it was necessary to stop the advance of General Varela's troops of the Army of Africa.

The persistence and tenacity of both sides in the battle meant an inflection point in the Spanish Civil War, partly because it was the first time that Franco's troops were stopped.

The confrontation involved the participation of troops that belonged to the newly formed International Brigades, as well as heavy military materiel from the Soviet Union.

This first frontal attack was very bloody on both sides and involved a slow advance of the central axis of effort through the Casa de Campo to a stream of the river Manzanares.

Both sides began to run out of tactics as the death count rose, and the battle was carried out between the faculties and diverse buildings on the campus.

Even though the front stayed the same, there was a fierce battle in the Ciudad Universitaria and Parque del Oeste with mines and countermines, all with unsuccessful infantry offensives until 28 March 1939, when the colonel Segismundo Casado surrendered the city to the attacking troops.

The war caught the university in the middle of a transition period, since many of the faculties that were in the urban center were slowly integrating with the newly-built campus.

The scars that the battle left have been hidden by the reconstruction of the faculties and the rebuilding of the surrounding Moncloa-Aravaca district, as well as the consequences of the urbanization of the 1970s, and remodeling projects like the burying of the M-30 and the creation of parks on the shore of the Manzanares like Madrid Río.

From the beginning of November the area became a prolonged battlefield, and many of its buildings were seriously damaged in the battle, the philosophy and letters faculty being the most affected.

The testimonies of the destruction were gathered from brigade members who fought in the war, like John Sommerfield, Dan Kurzman, Bernard Knox, and writers like Marta Torres Santo Domingo.

During the rest of the conflict, many trenches, gun nests, refuges of all types, and bunkers were built throughout the campus area, even though the front suffered almost no changes.

There were a few buildings in the area, despite only having been built four faculties (Medicine, Pharmacy, Science and Philosophy) and the Architecture, Veterinary and Agrarian Engineers.

Thanks to the operations of the combat engineers colonel Tomás Ardiz Rey in collaboration with Carlos Masquelet, the Casa de Campo, the Moncloa zone and the Ciudad Universitaria became stronger.

Between the Casa de Campo and the Ciudad Universitaria, the Manzanares' river bed in 1936 had abundant vegetation from the Pardo mountain.

The channeled zone was heavily defended, was very dangerous for the attacking forces' infantry, and made the passing of the tanks difficult.

For example, the viaduct of the Quince Ojos that supported the road to La Coruña (surpassing the hill of the Cantalasranas stream), just like the Aire bridge.

The Republican militias aimed to defend the capital at any price, stop the advances of General José Varela columns, and prevent the fall of Madrid into Nationalist hands.