Unknown author · Public domain

Clara Immerwahr became the first woman to earn a doctorate in chemistry from the University of Breslau, at a time when German universities barely admitted women as students. She was married to Fritz Haber, and spoke out against his chemical-weapons research as a "perversion of the ideals of science"; ten days after he oversaw the first large-scale chlorine gas attack at Ypres in 1915, she took her own life with his service pistol. The exact motives were never fully documented, but her opposition to that work is the connection historians have long drawn.