When, in 1914, Mgr. Ratti became Prefect of the Vatican Library, he brought to the task all his previous preparation under his great and venerated master, Ceriani, and his subsequent training in the management of the great Library at Milan. During the turmoil of the War, the new Prefect was able to stand aloof from all party politics and parties, and proved himself the humble follower of the impartial attitude of the Vatican. When the Armistice put an end to the strife of nations, he threw himself into the work of reconstituting the scientific international character of the relations of the Vatican Library with students of all countries.