According to history, yoga began about 5000 years ago - but that’s a bit like saying Minnesota’s history began at the glaciers. With no disrespect intended, we’ll skip a bit and start with Krishnamacharya (1888-1989). Krishnamacharya’s legacy extends well beyond just the Ashtanga practice: his teachings shaped B.K.S. Iyengar, Pattabhi Jois, Indra Devi, and T.K.V. Desikachar and all the students who have followed these and other well known teachers.
Not much is known about Krishnamacharya. He was born into an India dominated by British rule where the practice of yoga had fallen into disuse. It was his father who set him on the yogic path when he was quite small, teaching him the Pantanjali’s Yoga Sutra’s and 24 asanas. When he was 16 he traveled to his ancestor’s shrine at Alvar Tirunagari, where he received a vision to continue in his yogic journey and education. Krishnamacharya did so by exploring Indian clasical disciplines, obtaining degrees in philology, logic divinity and music and by seeking out and finding the well known teacher, Sri Ramamohan Brahmachari, one of the few remaining classical Hatha instructors.
Krishnamacharya spent seven years with Brahmachari, memorizing Pantanjali’s Yoga Sutra’s and studying asana and pranyama practice. In return, Brahmachari requested that Krishnamacharya return to his homeland, teach yoga, and start a family. This may seem like an odd request since at that time traditionally yogis were renuciates, but his guru wished for Krishnamacharya to understand family life and teach a type of yoga that benefitted the lay person.
Over the coming years, during periods of poverty and prosperity, he gradually built up his teachings and practice, his main pupils being young boys (remember, women were not taught yoga in India). Krishnamacharya pulled from many disciplines: yoga, Indian wrestling, and gymnastics to develop a very fluid practice aimed at building physical fitness. Over these years he met and taught Pattabhi Jois, B.K.S. Iyengar, Indra Devi, and Krishnamacharya son’s T.K.V. Desikachar. While each would continue on to develop their own styles their initial instruction was all from a common source.
As quoted from Yoga Journal, "He was a pioneer in refining postures, sequencing them optimally and ascribing therapeutic value to specific asanas. By combining pranyama and asana, he made the postures and integral part of meditation instead of just a step leading toward it."
Krishnamacharya continued to modify and change his instruction over the coming years. He emphasized that yoga could serve any creed and adjusted his teachings to respect each students faith as he interacted more and more with westerners. He became known as a great healer in India, using yogic techniques to help heal stroke victims and others with infirmities. In some ways, he reinvented himself to be able to bring yoga to the common person.
Here is a U-Tube Video from 1938 with Krishnamacharya demonstrating yoga.
Yoga Journal, "Krishnamacharya’s Legacy", Fernando Pages Ruiz. May/June 2001. Pages 96-101.
Ashtanga: Practice and Philosophy, Gregor Mahlor.
Astanga Yoga As it Is, Matthew Sweeney. (Not a misspelling, a different spelling.)
(This is based off of the research I have done with the resources available to me. There may be more accurate information on this and many of the topics forthcoming and I certainly welcome any feedback concerning potential inaccuracies.)