The first Hindu teacher to actively advocate and disseminate aspects of yoga, not including asanas, to a western audience, Swami Vivekananda, toured Europe and the United States in the 1890s. The reception which Swami Vivekananda received built on the active interest of intellectuals, in particular the New England Transcendentalists, among them Ralph Waldo Emerson (1803–1882), who drew on German Romanticism and philosophers and scholars like G. W. F. Hegel (1770–1831), the brothers August Wilhelm Schlegel (1767–1845) and Karl Wilhelm Friedrich Schlegel (1772–1829), Max Mueller (1823–1900), Arthur Schopenhauer (1788–1860), and others who had (to varying degrees) interests in things Indian.
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According to Crangle, some researchers have favoured a linear theory, which attempts "to interpret the origin and early development of Indian contemplative practices as a sequential growth from an Aryan genesis",[note 4] just like traditional Hinduism regards the Vedas to be the ultimate source of all spiritual knowledge.[note 5] Thomas McEvilley favors a composite model where pre-Aryan yoga prototype existed in the pre-Vedic period and its refinement began in the Vedic period.
Ascetic practices, concentration and bodily postures described in the Vedas may have been precursors to yoga. According to Geoffrey Samuel, "Our best evidence to date suggests that [yogic] practices developed in the same ascetic circles as the early sramana movements (Buddhists, Jainas and Ajivikas), probably in around the sixth and fifth centuries BCE."
The Maitrayaniya Upanishad, likely composed in a later century than Katha and Shvetashvatara Upanishads but before Patanjali's Yoga Sutra, mentions sixfold yoga method – breath control (pranayama), introspective withdrawal of senses (pratyahara), meditation (dhyana), mind concentration (dharana), philosophical inquiry/creative reasoning (tarka), and absorption/intense spiritual union (samadhi).
Theosophists including Madame Blavatsky also had a large influence on the Western public's view of Yoga. Esoteric views current at the end of the 19th century provided a further basis for the reception of Vedanta and of Yoga with its theory and practice of correspondence between the spiritual and the physical. The reception of Yoga and of Vedanta thus entwined with each other and with the (mostly Neoplatonism-based) currents of religious and philosophical reform and transformation throughout the 19th and early 20th centuries. Mircea Eliade brought a new element into the reception of Yoga with the strong emphasis on Tantric Yoga in his seminal book: Yoga: Immortality and Freedom. With the introduction of the Tantra traditions and philosophy of Yoga, the conception of the "transcendent" to be attained by Yogic practice shifted from experiencing the "transcendent" ("Atman-Brahman" in Advaitic theory) in the mind to the body itself.