son was only a few months old. When he was in the country, he often spent lunch hours and evenings at work or with his colleagues rather than at home. In a 1915 letter to Setsuro Tamaru, a Japanese colleague of Haber's, Immerwahr expressed her disappointment that her husband worked "18 hours a day, almost always in Berlin (not in Dahlem!)" During World War I, Fritz Haber became a staunch supporter of the German military effort and played an important role in the development of chemical weapons (particularly poison gases). His efforts would culminate in his supervision of the first successful deployment of a weapon of mass destruction in military history, in Flanders, Belgium, on 22 April 1915. Immerwahr reportedly spoke out against her husband's research as a "perversion of the ideals of science" and "a sign of barbarity, corrupting the very discipline which ought to bring new insights into life." Immerwahr was also a witness to the accidental death of one of her former college classmates, Otto Sackur, who was attempting to tame cacodyl chloride in Haber's lab as part of Haber's research into chemical weapons. Death Shortly after Haber's return from Belgium, Immerwahr shot herself in the chest using Haber's military pistol. On 2 May 1915, she died in her son's arms. The morning after her death, Haber left for the first gas attack against the Russians on the Eastern Front. Her suicide remained largely in the dark. Six days after her death, only the small local newspaper Grunewald-Zeitung reported that "the wife of Dr H. in Dahlem, who is currently on the front, has set an end to her life by shooting herself. The reasons for this act of the unhappy woman are unknown." There is no evidence of an autopsy. The poorly documented circumstances of her death have resulted in considerable discussion and controversy as to her reasons, including that she opposed Haber's work in chemical warfare and her suicide was a response to him personally overseeing the first successful use of chlorine gas during the Second Battle of Ypres, resulting in over 67,000 casualties. Immerwahr's ashes were moved from Dahlem to Basel and buried together with Haber's after his death in 1934. Subsequently, their son Hermann Haber emigrated to the United States, where he committed suicide in 1946. In drama, fiction and writing A number of works have been inspired to explore Fritz and Clara's