Fritz Haber

After the war, Haber did not renounce the principle of chemical warfare and continued his scientific activities in Berlin. In 1933, the Nazi regime's antisemitic laws forced him to part with Jewish colleagues and made his own position untenable; he resigned and left Germany.

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Documented

Attribution

Directly implicated

Haber received the 1918 Nobel Prize in Chemistry for ammonia synthesis. The award prompted intense international controversy because of his central role in chemical warfare and Allied allegations portraying him as a potential war criminal.

State of the evidence

Documented

Under Haber, the Kaiser Wilhelm Institute became a major military research centre for chemical agents, dispersal methods, toxicology and protective equipment. It mobilised hundreds of scientists and a substantial support workforce.

State of the evidence

Documented

Haber played an essential role in preparing the chlorine attack of 22 April 1915 at Ypres, supervising the system's scientific and meteorological aspects. According to historical summaries, the attack caused at least approximately one thousand immediate deaths and several thousand injuries, opening a new phase of chemical warfare.

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Directly implicated

Clara Immerwahr, a chemist and Haber's wife, died by suicide a few days after the Ypres attack. A popular account portrayed her act as a protest against her husband's work on chemical weapons, and their relationship was evidently troubled.

State of the evidence

Disputed

Haber joined German intellectuals who signed the Manifesto of the 93, a text defending Germany against accusations of brutality and affirming the unity of German culture and militarism during the First World War.

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Attribution

Directly implicated

The industrial synthesis of ammonia developed by Haber and subsequently industrialised with Bosch enabled mass production of fertilisers, but also gave Germany a domestic source of nitrates needed for explosives during the First World War blockade.

State of the evidence

Documented

Attribution

Directly implicated