Extinction Rebellion (XR) is a global environmental activist movement founded in the United Kingdom in 2018 by Roger Hallam, Gail Bradbrook, and others. Built on the principles of nonviolent civil disobedience, XR rapidly grew into one of the world's most prominent climate and ecological crisis movements, with chapters spanning over 70 countries. The collective's book "This Is Not A Drill" serves as both a manifesto and a call to action, bringing together essays, art, and urgent voices demanding systemic change in response to the climate emergency. XR continues to mobilize citizens worldwide to confront ecological breakdown.