Below is a timeline of important yoga texts having an emphasis on hatha yoga.

1800-1000 BCE RG Veda 

There are four Vedas; Rigveda, Samaveda, Yajurveda, Atharvaveda. They are said to be sruti, heard – of divine revelation (as opposed to smriti, remembered). They contain the foundational understanding of the sanatana dharma, the basis of all proceeding yoga thought. All schools that acknowledge the primal authority of the vedas are known as orhadox.

The vedas involve collections of mantras to be memorized and chanted. (in very precise tones – for the meaning of the word is the sound itself). The Rigveda is the oldest and largest. It is also considered the most important. The vedas are the oldest recorded religious texts. They stem from the Indo-aryan culture based around the Indus Valley in Northern India.

Much of the instruction is to do with rituals for the sake of pacifying and pleasing the gods. Here, the gods are older ones, such as agni, indra and rudra. The instruction was conveyed in a complex and symbolic language as hymns. The Upanishads are fundamental in unpacking the philosophical and metaphysical teaching of the vedas – hence their importance. The veda are also the origin of the much maligned caste system of India.

There is mention of yoga in The Vedas. However, as the scholar David G. White has popularized, here yoga stands for the rigging or hitching-up of the chariots for battle. To which end, many scholars disqualify this early mention as redundant. However, White takes it to be a simile for the inner-methodology at work in yoga of super-charging the body. The chariot being the most complex thing at the time, so the apt metaphor for this process.

1000-500 BCE Mahabharata (including The Bhagavad Gita)

The text centres around the Kurukshetra war. The battle for the throne of Hastinapurais between two branches of a ruling family, the Pandavas and the Kauravas. The primary message of the text is regarding the importance of doing ones’ duty; dharma. It’s an epic story, of which the `Bhagavad Gita is central as the kind of philosophical teaching part. Krishna gives a discourse to warrior Arjuna. He has seemingly lost his way on the battlefield, about the importance of dharma.

In part, we find a conservative, Brahmanical attempt to preserve the status-quo and keep everyone in their place. That is, to keep the caste (‘varna’), system in tact. We also find a most democratic belief that everyone can take charge of their own spiritual path. That one does not necessarily need scriptural knowledge or recourse to a brahman to find ones’ own salvation.  It would be to do a disservice to reduce The BG to simply this endeavour of keeping the social order. For, it ranges over a whole number of methodologies for yoga, much of it personal instruction for the individual.

Which, indeed, is one reason the book has stood the test of time. It acts as a kind of summary of many different approaches to the ideas involved. In addition gives methods for achieving; yoga up to that date. And, by this time yoga does clearly mean yoga. Specifically, in The BG, the attempt to concentrate the mind through meditative techniques. The aim being for it to remain fixed on one-pointed perception in the restraint of the senses. It also considers Samkhya philosophy. This is the gunas, and, the dualistic nature of material reality, split between purusha and prakriti.

Bhakti Text

However, it is primarily a bhakti text. We hear the constant injunction to; keep your mind focused on Me. The discourse contains a number of passages that specifically mention some degree of physical methodology. This is hatha yoga in the use of breathing and steady and aligned spine. The text has been generally taken, correctly, as a manual for the yoga of devotion (bhakti).

Nevertheless, we still find a clear presentation of the other fundamental methods of yoga; laya, raja, and, as mentioned, hatha. In the second chapter a concise and very approachable metaphysical overview for yoga-thought, detailing the laws of karma and reincarnation. Indeed, it is the correct understanding of karma that underpins the foundational dharma-teaching of the text. If the individual is influenced by forces beyond their immediate control, the kind of individualistic and reactive thinking that Arjuna shows in the opening chapter is inevitably deeply mistaken.

900-500 BCE Brahmanas

The Brahmanas further clarify the ritual of the vedas. As well as this, they are particularly noted for their explanation of symbolism found there. They are also said to be sruti, ‘heard’; that is, divine revelation. Each of thefour vedas has a particular Brahmana associated with it, as a kind of further qualification if its’ meaning. Accordingly; Rigveda – aiteraya, Samaveda- sadvimsa, Yajurveda – shatapatha, and the Atharvaveda – gopatha.

Here, the aim is clearly transcendental; liberation from this world and the suffering entailed. The Brahmanas are also theistic; liberation involving union with god. At this time, however, the method is generally found to revolve around the finer details of ritual and sacrifice. Hence, the texts’ emphasis on mantra. The teaching is often conveyed through the use of myth. The gods are still the ancient ones. Principally, Indra, Agni and Soma and the aim is still in pleasing them through ritual worship. In doing so, being granted (by them) success in ones’ objectives – both worldly and otherwise.

600 BCE Early Upanishads

The Upanishads are notoriously inconsistent. Having been the result of mainly oral-transmission over a lengthy period it is composed by various authors. Therefore, subject to a whole range of different influences. You can find a whole scope of different and often conflictive philosophical perspectives in these texts. As such its’ not easy to generalize on them. What we can say, is that ubiquitous to the Upanishads is the concern with atman and brahman, spirit and god. Moreover, the non dual, that is advaita teaching that since in atman is the individual spark of brahman. This is god is contained within the individual, hence god and individual are one. It is here than that originates the well-known phrase; tat tvam asi; ‘though art that’.

The Upanishads are also characteristically mystical in nature. Atman not being able to perceive the nature of brahman on its own terms, through the individual-mind. This is where meditation, or alterted states of perception start to become prevalent. Is is as an approach to the problem of life. One translation of the word Upanishad is ‘revealing underlying truth’. (‘as well as ‘sitting down near to’ being the more commonly heard one). The Upanishads aim then, is both self-knowledge (of atman realizing it is brahman) as well as still being clearly transcendental. For, atman knowing itself as brahman, unites and is absorbed with, Brahman. Hence ending the duality of material existence.

Each Upanishad is embedded in one of the four-Vedas. To which end, they provide the philosophical part; the qualification of the metaphysical underpinnings of the Sanatana Dharma. There are as many as 180-200 upanishads. All are said to be sruti (revealed), as part of the vedas.  However, there are generally agreed to be 13 principal ones.

Here is a short overview and summary of these:

• Brhadaranyaka Upanishad: Part of the Yajur Veda. It teaches, amongst other things, about the nature of atman.
• Chandogya Upanishad: repeats part of the previous Upanishad, this is where the renowned phrase tat tvam asi orginates.
• Taittiriya Upanishad: part of the Yajur Veda; continues with the theme that duality is an illusion.
• Aiterya Upanishad: part of the Rig Veda, it emphasizes the joys of living a life according to dhamra.
• Kaustitaki Upanishad: part of the Rig Veda, continues themes of ending duality and the unity of all existence.
• Kena Upanishad: part of the Sama Veda. The idea that one can only understand brahman through self-knowledge as opposed to scriptural-study is particularly pertinent.
• Katha Upanishad: part of the Yajur Veda, here one can find a good discussion on the concept of moksha.
• Isha Upanishad: part of the Yajur Veda, it focusses particularly on karma related to dharma.
• Svetasvatara Upanishad: part of the Yajur Veda. Of specific interest here is the need for self-discipline in the path towards Brahman.
• Manduka Upanishad: part of the Atharva Veda. The text disstinguises intellectual knowledge, lower knowledge, from the higher knowledge of self-understanding.
• Prashna Upanishad: Part of the Atharva Veda it discusses the human condition, with devotion, bhakti being offered as the solution.
• Maitri Upanishad: Part of the Yajur Upanishad. It explains the ways people suffer in life, the means offered being liberation by self-realisation.
• Mandukya Upanishad: part of the Atharva Veda discusses the sacred syllable OM. Stresses the importance of detachment.

500-300 BCE Ramayana

The Ramayana, means Light within me (ra=light, ma=in my/in my heart).  It’s an epic-style story in which the king, Rama, the hero, must rescue his beloved Sita, from Lanka. She has been kidnapped and taken by the evil Ravana. This is finally achieved by the Kings’ beloved and devoted servant Hanuman (the monkey-god). Incredibly popular up to this day in India, this is a story that pretty much everyone knows in detail.

Vivekananda, has it that this is an allegory where Rama stands for Brahman, Sita for Atman. Lanka is the body subject to The Gunas. Whereby, we achieve liberation by rescuing atman from the clutches of prakriti involved in The Gunas. Indeed, this is the simplest form of an allegory that has been extended much further by religious scholars. For, example, Rama is atman/spirit, Sita is chitta/mind, Hanuman is prana/life force, Lakshmana is conscious awareness and Ravana is ego.

For most, it’s a tale highlighting the need for courage and determinaton in the face of evil. Indeed, that it’s not simply good enough to be good (as Rama is), but, to actively oppose evil. Furthermore, it develops this through the character of Hanuman representing the importance of devotion and service.

Combined with the Mahabharata, the two texts are taken as the Vishnu Purana, Rama being worshipped as an incarnation of the god Vishnu. As with the Mahabharata, the ultimate, underlying theme is always the preservation of dharma, of which, Rama is seen as the embodiment of this principle.

200 BCE-200CE Patanjali’s Yogasastra

Patanjali’s Yoga Sutras are still not often recognized to be part of a larger work along with The Yoga Bhashya; the commentary on these sutras. One which is said to be written by Vyasa, yet, most scholars believe was actually Patanjali. Therefore, as much as there are varied interpretations of this text due to how sparse it is, the meaning is clearly given in the commentary, as well as two later ones of importance (Vacaspati Misra’s and Vijnanabhiksu’s).

What is, however, up for debate is the dating of the text – Bryant has it potentially at the turn of the common era, whilst Phillip Mass as late as 400CE. Equally, the textual integrity, with some scholars seeing it as a joining of two different texts, one on ashtanga yoga and the other on kriya yoga. That is, that the ubiquitous eight limbs of yoga taught on every YTT, may, in fact, be a Buddhist interpolation in a text on Samkhya and Kriya yoga.

The text is a classic representation for the most part of the philosophy that generally underpins that of the Sanatana Dharma, namely, Samkhya. We find a strongly dualistic view in the yoga sutras that has Patanjali explain to his reader the goal of transcending the material realm through discrimination, jnana yoga. On the other hand, it is rather unique as a Samkhya text in emphasizing to such a great degree the Isvara or god principle as important.

There are 4 chapters or padas in The Yoga Sutras. They are, Samadhi Pada, laying out the fundamental, metaphysical view. Sadhana Pada, that which describes how to practice, Vibhuti pada; strangely, a whole chapter on the special-powers (Sidhis) that come from practice, and Kaivalya Pada, that delves deeper into the state of liberation and the aspect of meditation that precedes it.

200-900 CE Puranas

The Puranas are a huge grouping of Indian texts – rather like The Vedas. The difference between the two being that The Vedas is exclusively religious writing, whereas the puranas cover legends, folklore, grammar, cosmology, astrology and medicine, as well as a whole range of other subjects.

Indeed, the range of topics this literature spans is encyclopedic. Hence, the meaning of Purana, simply old, denotes its’ generality in focus. There are 18 major (Mukhya) Puranas and 18 minor (Upa). All named after gods, perhaps the most well known is The Bhagavata Purana. This has been interpreted widely; both as advaita (dual) and dvaita (non dual).

Traditionally a Purana is said to teach the nature of the universe from creation to destruction under five subjects of signs; primary creation, secondary creation, genealogy of the gods, the reign of humans and the solar and lunar dynasties. These texts are particularly central in those schools involved in the Bhakti path of yoga as they elaborate in great detail many stories of Krisha as a young boy, central to these traditions based on devotion.

200 CE Samkhya Karika

This is a fundamental text, as the oldest surviving text explaining the Samkhya philosophy, which, basically, is the fundamental underpinning of all viewpoints that have come to be known as Hindu. The aurhor is said to be one Ishvara Krishna (not the god), and, again, there are a number of related commentaries of primary importance; particularly, Gaudapada’s Samkhya karika bhasya.

The text lays down the framework of Samkhya. It explains the duality of Prakriti and Purusha, the nature of the evolutes – how from Mahat the great principle, comes the 24 tatvas, the 3 gunas of rajas, tamas, and satva, the nature of direct perception through buddhi and the quality of purusha, or the atman.

In short, along with the Yoga Sutras, although the two texts have no direct relation, one can get a fair idea of the yogic viewpoint, the reason for our suffering and the means to end it. “Samkhya” means numbering. Indeed, it is through the means of categorization, that is, jnana yoga, the yoga of correct perception or discrimination is the essential yoga of Samkhya.

Which, to this end can get quite complex; for example; with the 24 tatvas divided into ahamkara, Mahat, prakriti and citta, then the 5 karmendriyas, then the jnanaendriyas, the 5 tanmatras and the 5 elements…

1000-1100 CE Amanaskayoga

This short text is the first text to teach a yoga referred to as rajayoga. A Shaivite and tantic based texts, it details the practice of sambhavi mudra. This is a basic form of meditation practice based on the aim of no mind as suggested in the name of the text (a mana). Here, the aspirant sits down and stills the mind. Indeed, the instruction is very basic; unusually, for a text emanating from a tantric background, there is little focus on what was then hathayoga; basically, the science of pranayama.

Written as a dialogue between Isvara and Vamadeva, this is then a text not only on the yoga of meditation, that is, raja yoga, but, in its method of dissolving the mind and breath, a laya yoga oriented text. In other words, one instructing the ‘yoga of dissolution’. The Amanaska was one of the sources of the most influential texts of the medieval period on hatha yoga the hathayogapradipika.

On the other hand, it rejects the auxiliaries of yoga – that is breath and mudra, along with any ascetic or tapas based practices. Indeed, the term amanaska in medieval times was not used to denote a system of yoga, rather the state of samadhi. Hence, this text really cuts to the heart of the matter in a most direct and economical way. The text has never been clearly designated to an author, although often assigned to goraksanatha. For a most detailed explanation of the text see Jason Birch’s The Amanaska: King of all Yogas’.

1000-1100 Amrtasiddhi

The earliest substantial text on Hatha Yoga, although it doesn’t actually mention it by name. The text focusses on the role of bindi in the body; that is the way to preserve this vital essence by essentially tantric or alchemical means.  To this end, it focusses on the particular practices known mahamudra, mahabandha and mahaveda.

These have Buddhist origins, potentially originating within the Vajrayana Tibetan Buddhist lineage, where you can still find the practice today. Indeed, the original manuscripts are both found in the Sanskrit and Pali language.

From ‘a-mrta’; not subject to death, the text centres on how to attain immortality through the union of prana and apana, or, the reversing of the bindi as it drips down from the crown of the head. This is explained through the recognisably tantric symbolism of sun, moon and fire. By cancelling out the burning of the moon by the sun, one attains liberation from death.

The three practices:

Mahamudra; after inhaling, the breath is held, whilst placing the heel under the perineum and catching the extended foot (a kind of Janu B).

Mahabandha: A combination of mula and jalandara bandha which forces the breath into the central channel.

Mahaveda: whilst taking two hand-gestures (mudras) the aspirant keeps raising themselves up and down, hitting the heels on the perineum.

James Mallinson has done outstanding work on this text for those that wish to study it further.

1200 CE Dattatreyayogashastra

Here we find a combination of raja and ashtanga ( 8 limbed yoga method). In its detail, it is the same ashtanga yoga Patanjali famously details. Indeed, the text is quite a fusion; a vaishnaite text it teaches a type of hatha yoga aiming at the raja yoga goal of samadhi. This is put forth as to be done by three methods; mantra, laya as well as hatha yoga.

Attributed to the sage Kapila this is where we clearly see the development of hatha yoga per se. For example, the text states that there are 84,000 asanas (though it only actually lists two; savasana and viparitakarini (an inverted position much like sarvangagasana). It also lists two pranayamas (antar kumbaka as well as a form of nadi shodana), along with numerous mudras.

Indeed, it is here that we find some of the earliest mentions of kechari and vajroli mudras, along with jalandhara, uddiyana and mulabhanda for the purposes of preserving bindi. The earliest text to name  these various activities as hatha yoga, once again, James Malinson has written an incredibly informing article on this text.

1200 CE vashishtasamhita

This text, ascribed to the sage Vasishta (actual author remains unknown) is perhaps the earliest to detail more dynamic asanas – ones’ that were not seated and more like mudras – such as kukkutasana and mayurasana. Here its descriptions are produced ad verbatum in the later hathayogapradipika.

1300-1400 yogabija

The Hathapradipika incorporates 18 verses of the yogabija. Similarly to the Dattatreyayogashastrathe yogabija teaches four methods of yoga; mantra, laya, hatha and raja. Here we find the first etymologicial definition of hatha yoga as sun-moon; relating, once, more to the texts’ concern with preservation of the vital essence, or bindu, in the body (bija; seed, semen).

A definitively tantric text in its approach, it actively scorns jnana yoga as unsuitable for attaining the aimed-for goal in liberation. Indeed, this is the first text wherein we start to see the tensions between yoga and Vedanta emerge.Instead, it lists a number of other, more active techniques, such as pranayama and laya yoga – the willful dissolution of the mind through meditative methods. 

The text is considered to be an important early text on this subject of hatha yoga attributed to the nath sampradaya. Whilst the aim of liberation remains the same, the methodology is quite forcefully stated to be necessarily physical; that which affects alchemical change in the human body. Namely, the movement of kundalini through sushumna nadi.

Once again, however, the hatha yoga detailed here is predominantly that of the combination of pranayamas and mudras to pierce the psychic gnots granthis’ in the spine, leading to the free flow of kundalini.

1450 Hathapradipika

Evidently, the most well-known text on hatha yoga in a form recognizable to the way we understand it currently. Authored by Svatmarama, who is said to trace his lineage back to the original yogi Matseyendranath, there are various copies of this text, all differing slightly from one another.

However, the essential framework remains the same; through breath restraint done through the use of asana and mudra and, of course, pranayama. Then, mind is brought into obeisance and the goal of raja yoga, liberation is achieved. This is done through meditation made possible by the concentration of the mind through the afore-mentioned techniques. 

It is in this text that we also find more detailed description of a range of yoga asanas (18 in total and including more dynamic postures such as mayurasana). Along with detailed instruction on the shatkarmas, this is probably the earlies mention of hatha yoga as a physical form of therapy aiming at facilitating physical health (not only energetic transformation), for the sake of producing an uninterrupted ability to meditate in the practitioner.

The hathayogapradipika is, once again, a mix of a raja yoga text (in its aims and emphasis on the final goal of meditation) as well as a hatha one. In it we find a detailed overview of the yogis inner-universe of chakras, nadis and prana. We also receive the most specific instruction yet for the practice of hatha yoga, including instructions on how to practice (essentially by leading a modest life), as well as the obstructions to practice in not adhering to his rules.

This is an essential reading for anyone interested in the evolution of hatha yoga and one that The Hatha Yoga Project have covered in detail, along with Jason Birch’s current project on the same.

1500-1800 Shivasamhita

Written by an unknown author, the text is based around the lord Shiva addressing his consort Parvati. Hence the name; Shivas’ compendium. The Shivasamhita is one of three texts, along with the hathapradipika and gherandasamhita that are commonly taken to be the fundamental medieval texts on hatha yoga.

On the other hand, in the first chapter it concentrates on an explanation of the non-dual philosophy known as advaita-vedanta. It is only after this that it returns to the subject of the complex yoga-physiology of kundalini and the complicated interrelations as to how to facilitate its’ arousal. Nevertheless, the text is unique and specific in recommending that all householders ought to practice this version of hatha yoga.

Another notable inclusion in the text is the practice of nada yoga or the focus on sacred sound as a form of meditation. There is said to be a distinct Buddhist influence running through the text. Eight-four asanas are detailed in the text, yet, only four are actually explained in any detail.

1500-1600 Yogacintamani

In this text we find thirty-four asana’s described in detail. Kukkutasana along with mayurasana are featured amongst what starts to become a more physically dynamic approach to yoga asana.

The text borrows extensively and directly from the hathapradipika. However, its primary orientation is on the science of Ayurveda. The author is Harthsakirti Suri, and in it, it details the ashtavidha pariksha, or, eight types of examination of a patient. Namely; pulse, urine, eyes, oral, tongue, stool, voice and touch.

It is as this point then we find the term hatha yoga clearly presented as one incorporated into a general therapeutic modality. Jason Birch has elaborated more on this text.

1600-1700 Gherandasamhita

Authored by Srisa Chandra Vasu it means Gheranda’s collection. The text details a sevenfold yoga (in contrast to Patanjali’s ashtanga). This involved; shatkarma, asana, mudra, pranayama, pratyahara, dhyana, samadhi. The purpose then being to use asana once again for the sake of the ultimate aim of meditation, dhyana.

Considered a textual demonstration of classical hindu philsophy, the tendency is towards cleaning up the more transgressive presentation of hatha yoga, aiming instead towards the primary focus on the purification of the body. However, it is probably contains the most encyclopedic presentation of hatha yoga so far, although, calling it ghata yoga, not hatha.

Along with the Shivasamhita and hathapradipika it makes up the triad of fundamental texts on hatha yoga of the medieval period. Hence, an incredibly important text, its detailed presentation of the techniques of hatha is instrumental to our modern understanding, although is noticeably quiet on yama and niyama.

A dialogue between Gheranda and Chandra, as is so often the case with these texts, it suggests the idea that the text has been secretly overheard and then written down.

1800 Sritattvanidhi

A compendium commissioned by Krishnaraja Wadiyar III, the Maharaja of Mysore. In fact, he is stated to be the designated author. This text is thought to have drawn heavily from the hathabhyasapaddahti and presents an illuminated manuscript of 122 asanas.

More recently the subject of the book the traditions of the Mysore Palace, by Norman Sjoman (1998), he suggests the direct influence of this text over the teachings of Shri Krishnamacharya detailed in his first book The Yoga Makaranda.

1934 Yoga Makaranda

Authored by Shri Krishnamacharya the text lays out in pictural form and accompanying instruction a practice that groups asanas into sequences very similar to those of the ashtanga yoga we know today. Here, we find the emphasis on the technique of trishtana; breath, bandha, Drishti as well as the ‘counting method’ known now as the vinyasa count.

The book opens with a brief description description of why yoga should be practiced and its context within the classical ashtanga yoga of Patanjali. It also mentions and goes into some detail on the subject of mudras, chakras, shatkarmas, etc. In short, annexing Patanjali to more familiar hatha yoga concerns as Krishnamachaya was inclined to do.

The rest of the text is taken up with the 42 asanas of which Krishnamacharya himself is pictured doing most of them. Written during the period Krishnamacharya was under the patronage of the then Maharaja of Mysore, it is likely to be somewhat influenced by the concerns of the Maharaja at the time to popularize and modernized and approachable form of hatha yoga.

Krishnamacharya attributed the book to the text of the mythical Yoga Kurunta, one that he studied in detail in the time he claimed to have been studying in the Himalayas with his guru Rama Mohan Brahmacharya. On the other hand, as above, it seems more likely to have drawn the bulk of its influence from the shritattvanidhi.