Short answers, pulled from the story.
Environmentalism is a broad philosophy, ideology, and social movement about supporting life, habitats, and surroundings. It advocates the preservation, restoration, and improvement of the natural environment and critical earth system elements such as the climate. At its crux it attempts to balance relations between humans and the natural systems on which they depend.
The earliest ideas of environmental protectionism are found in Jainism, a religion from ancient India revived by Mahavira in the 6th century BC. The friar Francis of Assisi expressed reverence for nature in his poem Canticle of the Sun as early as 1224. The origins of the modern environmental movement lay in the response to smoke pollution during the Industrial Revolution.
John Muir and Henry David Thoreau made key philosophical contributions to environmentalism in the United States in the late 19th century. Muir lobbied congress to form Yosemite National Park and set up the Sierra Club in 1892. Thoreau published his experiences living close to nature in the book Walden.
Rachel Carson's 1962 book Silent Spring linked declining bird populations to the insecticide DDT and sold over two million copies. It questioned releasing large amounts of chemicals without understanding their effects on health and ecology. Public concern helped lead to the creation of the United States Environmental Protection Agency in 1970, which banned the agricultural use of DDT in the US in 1972.
The first Earth Day was celebrated on the 22nd of April 1970, to give awareness to environmental issues. Its founder, former Wisconsin Senator Gaylord Nelson, was inspired after seeing the 1969 oil spill off the coast of Santa Barbara. Earth Day is now celebrated in more than 192 countries every year.
Every year, more than 100 environmental activists are murdered throughout the world. In 2014, 116 environmental activists were assassinated, and 185 in 2015. In 2022, Global Witness reported that more than 1,700 land and environmental defenders had been killed in the preceding decade, with Brazil, Colombia, the Philippines, and Mexico the deadliest countries.