Johannes Lepsius (15 December 1858, Potsdam, Kingdom of Prussia – 3 February 1926, Meran, Kingdom of Italy) was a German Protestant missionary, Orientalist, and humanist with a special interest in trying to prevent the Armenian genocide in the Ottoman Empire. He initially studied mathematics and philosophy in Munich and a PhD in 1880 with an already award-winning work. Lepsius was one of the founders and the first chairman of the German–Armenian Society. During World War I he published his work "Bericht über die Lage des armenischen Volkes in der Türkei" ("Report on the situation of the Armeni