Most researchers believe yoga is 5,000 years old, although evidence suggests the practice could go back 10,000 years. Historians divide the evolution of yoga into four periods: pre-classical, classical, post-classical and modern.
Yoga's origins trace back to northern India, where the term was first mentioned in the sacred Rig Veda text. The practice spread throughout Asia over the centuries, reaching Europe and North America in the late 19th century and early 20th century. Yoga gained significant attention in the West after Indra Devi, a yoga teacher, opened a yoga studio in 1947 in Hollywood. The studio drew many celebrities and future advocates.