In this post, I would like to summarize the historical development of Yoga, Tantra, and Vedanta in progressive order from ancient times until now. The duration mentioned in the respective periods is approximate and for easier understanding.

1. Pre-Vedic/Tantric Period (5000BC - 1500BC) –The evidence was found through Pashupati Seal (statue of Shiva in yogic posture) discovered at the Mohenjo-Daro archaeological site of the Indus Valley Civilization. No texts are available, but it is understood that the knowledge was mostly passed down orally to the coming generations.

• Yoga - Tantric Yoga – as depicted taught orally
• Tantra – Knowledge about building houses, etc.

2. Vedic Period (1500BC - 500BC) – It is estimated that Vedas were compiled around 1500BC. Some Yogic practices mentioned in Vedas are termed as Vedic Yoga. Tantra is intertwined in Vedas especially found in Atharva Veda. It discusses the magical charms, herbology, and Ayurveda etc. As time passed extreme orthodoxy started to take shape and gradually it started the decline of Vedas. Finally, the knowledge of Veda culminated in the form of Upanishads (700BC) and thus called - Vedanta (end of Vedas). However many of the Upanishads included both Vedic and Tantric philosophy. The orthodoxy also gave rise to other paths such as Buddhism and Jainism, some borrowed the knowledge of Tantra and used it.

• Yoga - Vedic Yoga included – Mantra, Prana and Dhyana Yoga practices
• Tantra – Magical Charms, Ayurveda, Herbology and other practices
• Vedanta – Birth of Vedanta, summarizes the highest philosophy of Vedas

3. Post-Vedic Period (500BC - 500AD) – This period of India is known for great Emperors - from Mauryan Empire to Gupta Empire. Chanakya was the kingmaker and founder of Mauryan Empire (326BC). Later, specially Gupta period between 320AD - 550AD is called the Golden Age of India and was marked by extensive inventions and discoveries in science, technology, engineering, art, dialectic, literature, logic, mathematics, astronomy, religion, and philosophy that crystallized the elements of what is generally known as Indian culture. Thus, the majority of Smriti scriptures were written during this time. From the invention of Zero to great epics Ramayana and Mahabharata, Bhagavad Gita to all kinds of Sutras, Vedantic to Tantric, Shastras to Puranas, commentaries, and reviews, finally all were written down. Great scholars such as Kalidasa, Aryabhata, Varahamihira, Vishnu Sharma and Vatsyayana were part of Gupta Empire. In general, it was known as the Puranic period, along with Tantric rituals & practices. Some of the powerful emperors like Ashoka favored Buddhism, others Jainism and Hinduism. Yogic and Tantric practices also continued in Buddhism and Jainism.  

• Yoga – Classical Yoga of Patanjali was introduced in Yoga Sutra
• Tantra – Majority of Tantra were written down in this era but not publicly practiced
• Vedanta – Commentaries and digests were written on Vedanta

4. Renaissance Period (500AD – 1000AD) -  It can be called a Renaissance period of Vedanta and Tantra. Adi Shankara (788AD) was one of the leading master and most influential figure in the recent history, who revived and restored the knowledge of Vedanta and also wrote tantric scriptures as well. Many other tantric masters and practitioners such a Sadyajoti, Vasugupta and  Abhinavagupta revived the tradition. It is important to note that during the same time Muslim invaders start to invade (712AD) and conquer some parts of North West India.

• Yoga – Four classic path of Yoga restored – Raja, Karma, Bhakti, and Jnana
• Tantra –Tantric philosophy and practices flourished, major debates started to happen
• Vedanta – The philosophy of Vedanta was revived to its glory, Matha (institute) and Swami order was introduced by Adi Sankara

5. Medieval Period (1000AD - 1757AD): - Islamic invasion continued to expand its territory from north of India to the rest, and by 1500AD, Mughals ruled almost entire India. In the due process, laws of the time forced people to gradually withdraw and hide the outward spiritual practices of Yoga and Tantra. Thus, due to fear of forced conversion, fines or financial burdens, and persecution, people started to turn towards inward practices. As time passed, the Tantric philosophical scriptures evolved in this era but left-hand path practices became more secret due to persecution. In the middle of all this, brave Tantric masters such as Bhojadeva, Khemaraja made a great contribution to tantric philosophy. In this era Nath tradition masters such as Matsyendranatha, Gorakhnath, Svatmarama gave the practices and knowledge of Hatha yoga, which is currently practiced around the world with different flavors. 

• Yoga – Hatha Yoga came into existence, practices were extracted from Tantra, classic path of yoga continued
  
• Tantra – Right-hand path philosophy & practices got a revolution but left-hand path practices became very secret due to fear
  
• Vedanta – The philosophy was maintained by masters and swamis

6. Colonial Period (1757AD – 1947AD): - During this time many great enlightened masters came into light such as Swami Ramakrishna Paramhansa, Swami Vivekananda, Ramana Maharshi, and Sri Aurobindo who not only propagated the spiritual knowledge of India but also used the spiritual knowledge to ignite the fire for India's independence. They used both Tantra and Vedanta philosophies. British persecuted left-hand Tantrics in this era, so they continued to practice in secret. Right hand Tantra and Vedanta practitioners continued to excel. Swami Vivekananda formally introduced Vedanta and Yoga to the USA in 1893. Today, Swami Sivananda and Sri Krishnamacharya lineage is a well-known name to any yoga practitioners around the world.

• Yoga – All classic forms of Yoga (Jnana, Bhakti, Karma, and Raja) started to flourish along with Hatha
  
• Tantra – Tantric practices were mainly practiced as rituals, right-hand path was practiced but left-hand path continued to be in secret
  
• Vedanta – Knowledge of Vedanta was formally brought to America by Swami Vivekananda

7. Modern Period (1947AD - Now): - After the second world war, India got independence in 1947. At present, a majority of visible Yoga practitioners, practice some form of Hatha Yoga in India and around the world, as it is easier to connect with the body. Modern Yoga Teachers mostly come from or trained by one or more teachers of Sivananda and/or Krishnamacharya traditions. Swami Rama was able to demonstrate scientific evidence of tantric yoga practices. Osho Rajnish used some tantric techniques and taught meditation practices. Maharishi Mahesh Yogi made a great contribution during this time by introducing Transcendental Meditation. Majority of Hatha Yoga practices in the USA and around the world only became more visible in the 1980s or later.

• Yoga – Majority of Yoga practitioners are doing Hatha Yoga based practices, then TM based Raja Yoga and Bhakti Yoga practices
• Tantra – Tantric practices are still part of rituals, many practices are a light version of Hatha yoga, a majority of people hardly even know the names of proper tantric texts, however slow introduction are in the process and right-hand path of Tantra is more emphasized. Though there is no fear of persecution for left-hand path in India however, practitioners continue to remain secret
  
• Vedanta – Many practitioners starting to study and appreciate the Vedanta philosophy

Summary

As you can see the philosophy and practices of Yoga, Tantra and Vedanta have been continued since its inception. However, as the time passed, first it started to face challenges due to orthodoxy, but later revived. Then a time comes when it blossomed and reached its peak. But during the Islamic and British period of India, which roughly accounts for almost 1200 years, pushed practices especially the external practices into the hide or secret. But, after the independence of India, it is gradually changing, however living in a suppressed state for over thousand years, it takes time to realize the true state of freedom. When Hatha Yoga practices came to the West, it started primarily appealed to the people due to physical fitness elements into it. Now it has become multi-billion dollars industry.  But for serious practitioner who is looking for a holistic approach, the tools of Tantra and knowledge of Vedanta, give the wings for Yoga practices to fly high beyond the fitness realm.