Environmentalism is a perspective that is usually portrayed in IPE textbooks as a relatively new one that has emerged in recent decades. But a number of thinkers in the pre-1945 period developed pioneering environmentalist ideas that gained considerable attention during the eras in which they lived. With differing degrees of commitment, these figures were united by their desire to curtail human-induced environmental degradation in order to foster more sustainable ways of living within the world economy. They disagreed, however, about the causes of, and solutions to, the environmental degradation they identified. Some combined their environmentalism with economic liberal views (Alexander von Humboldt, Stanley Jevons); others with neomercantilism (Henry Carey); still others with Marxism (Marx himself) and autarkism (Eve Balfour, Graham Vernon Jacks, Sada Kaiseki). Others promoted environmentalist ideas that did not fit well into any of those categories, such as the Lakotan cosmology of Black Elk, the “Cartesian” approach of Frederick Soddy, and the decentralist visions of Richard Gregg, Radhakamal Mukerjee, Lewis Mumford and John Ruskin.