How did an ancient Indian spiritual discipline turn into a GBP 20 billion-a-year mainstay of the global wellness industry? This comprehensive history sets yoga in its global cultural context for the first time. From arcane religious rituals and medieval body-magic, through muscular Christianity and the British Raj, to the Indian nationalist movement and the arrival of yoga in the twentieth-century West, we discover how the practice reached its present-day ubiquity and how it became embedded in powerful social currents shaping the world's future, such as digital media, celebrity culture, the stress pandemic and the quest for an authentic identity in the face of unprecedented change.