The following is a list of people whom I'd call the great pioneers of modern yoga-- teachers who changed the shape of the yoga world, from a "flat" existence in one corner of the map, to a rounded, global experience by countless cultures and people.
6 Pioneers of Modern Yoga
Patanjali (150 B.C.E.): Like Christopher Columbus, Patanjali is sometimes credited with "discovering" yoga; however, the truth is that people had already been practicing yoga for centuries before he collated the sacred teachings into an organized text called The Yoga Sutras.
Krishnamacharya (1880): Krishnamacharya believed yoga to be "India's greatest gift to the world," and through his teaching and, later, his disciples (Pattabhi Jois and B.K.S. Iyengar among them), he further developed the practice and disseminated it to a larger audience.
Paramahasna Yogananda (1893): Author of the book Autobiography of a Yogi, Yogananda moved to the United States in 1920 and is thereby credited with being the first Hindu teacher to make his permanent home in America. Yogananda had a brother who was also an influential yoga teacher and the guru of Bikram Chouhury, a popular and polarizing figure within the yoga community today and the first to franchise a style of yoga practice.
Pattabhi Jois (1915): The late Pattabhi Jois was one of Krishnamarycha's most recognized students. The creator of ashtanga yoga, Jois was the first yogi to accept Westerners as students at his ashram in southern India. Some of these students included Norman Allen, Sharon Gannon and David Life, of Jivamukti Yoga, Doug and David Swenson, Tias Little, and many others.
Maharishi Mahesh (1918): Perhaps best known for his mentorship of The Beatles and other celebrities in the 1960s, the Maharishi was the most visible yogi to travel and teach outside of India in his day.
B.K.S. Iyengar (1918): Like Jois, Iyengar is also part of Krishnamarycha's lineage. The living legend turns 92 in December. His books are among the most influential, accessible, and articulate yoga resources on the market. He trained several of modern yoga's top teachers including Boston's Patricia Walden.
For A Guide to Different Styles of Yoga, click here.