Gülhane Hospital's first active presence took place in 1909 when its physicians, who were transferred to the newly established Faculty of Medicine, made out the majority of the academic staff. During World War I, the hospital undertook important duties in the successful delivery of health services to the Ottoman Army, and in the treatment of wounded soldiers brought from the Battle of Gallipoli (1915–1916). During the occupation of Istanbul from 1918 to 1923, Gülhane Hospital was transferred to Gümüşsuyu quarter of Beyoğlu, Istanbul, and continued to serve during the Turkish War of Independence (1919–1922). Following the end of the occupation of Istanbul, the hospital returned to its previous location.