World War I: The library of the Catholic University of Leuven is deliberately destroyed by the German Army. Hundreds of thousands of irreplaceable volumes and Gothic and Renaissance manuscripts are lost.

The Sack of Louvain was the German assault on the Belgian town of Louvain, part of the events collectively known as the Rape of Belgium, taking place during the First World War. Over the course of several days of pillaging and brutality, 248 people were killed and 1,500 were deported to Germany where they were held at the Munster internment camp until January 1915. The Library of the Catholic University of Louvain was destroyed after it was set on fire by the occupying German soldiers and 1,120 of the 8,928 homes in Louvain were destroyed.