Vito Volterra (1880-1940) was an Italian mathematician and physicist. Today, he is mostly known for his work in mathematical analysis. He is one of the authors of the predator-prey equations. In the first world war, he was active in the development of airships. It was him who had the idea to use helium, instead hydrogen for airships. Hydrogen is highly flammable, helium is not. From about 1922, he took positions against the Fascists. In 19333, he refused to take an oath on Mussolini, and left Italy. He spent the last years of his life in Spain and France. Shortly before his death, he briefly returned to Italy.