
Classic Indian epics such as the
Mahabharata,
Ramayana, and the
Puranas -- as well as
shramanic (wandering ascetic, namely Buddhist and Jain) writings -- refer to many exotic "tribes" (classes of living beings), describing them as superhuman or subhuman.
Narrations regarding them are often mixed with mythology and fiction. These tribes include Gandharvas, Yakshas, Kinnaras, Kimpurushas, Rakshasas, Nagas, Suparnas, Vanaras, Vidyadharas, Valikilyas, Pisachas, Devas (within them Vasus, Rudras, Maruts, Adityas) and Asuras (within them Danavas, Daityas, and Kalakeyas.)
Mythological beings or humans?
From a historical point of view, these exotic "tribes" simply may have been social groups that did not interact frequently with mainstream culture so that knowledge of them was very limited. This would have spurred the invention of fables about them. One point of view is that they were aliens from distant planets or hybrid-humans who had mixed with otherworldly visitors. While this seems more plausible, it is completely unacceptable today and has made necessary the "mythological" label. The neighboring Greek Empire would have become quite familiar with these legendary beings. Thus, tales of nature spirits, fairies, nymphs, giants, dwarfs, chimeras, and entire demigod pantheons were handed down through Western channels. This point of view usually assumes that the exotic capabilities of such tribes, as described in classic literature, are accurate and to be taken at face value.

These exotic capabilities included the ability to:
In any case, these tribes had a profound influence on Vedic culture. But they remained separate from the culture — perhaps due to their geographic isolation from the rest of the world. The tribes' bases ranged from high mountains (such as the Yaksas and Rakshasas) to deep forests (such as the Vanaras). Or they were civilizations beyond the mainstream Indian civilization (as with the Devas and Asuras), which prevailed on the plains of the rivers Saraswati, Sindhu, and Ganges.
Gandharvas (Pali, Gandhabbas)
Gandharvas are described as fierce warriors who could challenge even the great Kshatriya warriors (such as the Sakyan Clan). They were skilled in art, music, and dance. Some Gandharva tribes were allied with the Devas and sometimes with the Yakshas. They inhabited the land to the north of Mt. Kailasa, close to the Deva territories. The name Gandharva might have been derived from the name Gandhara (modern Afghanistan), since they might originally have inhabited the inaccessible mountains of the Gandhara Kingdom. Later they might have spread to the Saraswati river (seen by Balarama during his pilgrimage over Saraswati). The Ramayana mentions a Gandharva kingdom named Sailusha near the mouth of the river Ganges. Ghandarva-shtan became Afghanistan. The city of Kandahar in Afghanistan is said to have been named after Gandhara.
Yaksas (Pali, Yakkhas)
The Yaksas were a tribe living in the area surrounding the Kailasa range of the Himalayas. Their king, Vaisravana or Kubera, was a worshipper of Shiva, whose abode is thought to be Mt. Kailasa.
According to the Ramayana,
Kubera established or rebuilt the kingdom of
Lanka (now known as
Sri Lanka) and
cohabitated with
Yaksa people (still extant aboriginal tribes distinct from the Sinhalese majority). Later on,
Kubera's stepbrother
Ravan (common father
Vishrava) took over
Sri Lanka. And on their father's request,
Kubera moved to the Himalayan region near Mt.
Kailasa.
KinnarasKinnaras are a tribe famed for their power of flight often spoken of along with the
Gandharvas and
Yakshas. The epic Mahabharata and the
Puranas describe regions north of the Himalayas as the abode of
Kinnaras. The
Puranas mention an
Asura with a horse head, known as
Hayagrīva (
Sanskrit,
Haya = horse and
grīva = head). This
Asura was killed by an
incarnation of Lord
Vishnu, who took a similar form. In
Egyptian sculptures, horse headed figures or warriors employing an elongated face mask are a common motif resembling the head of a horse.
This region was also the abode of a tribe called
Kambojas. They were fierce warriors skilled in horse riding and cavalry warfare. Some of them were ransacking tribes that invaded village settlements, raiding them using their skilled cavalry. Myths surrounding the
Kinnaras probably came from these ferocious warrior tribes, who terrorized the
Vedic settlements.
There is to this day a district named
Kinnaur (
Centaur?) in
Himachal Pradesh that is thought to be the domain of the
Kinnara tribes. The people there call themselves
Kinnaurs.
Kimpurushas
Kimpurushas were described as lion-faced beings. They are often mentioned along with
Kinnaras. Some of the
Puranas consider
Kinnaras and
Kimpurushas the same, whereas the Mahabharata contains passages where they are distinct.
RakshasasRakshasas (modern Yetis) are described as having large bodies, probably due to their continuous life in cold climates over snow-covered mountains. There is speculation based on the
genographic project that many species of humans coexisted in a culturally evolved state.
Rakshasas may be one of these human species (like
Neanderthals in
Europe and
Asia with low
temperatures such as the Himalayan region) reduced to small pockets like the high Himalayas and the cool mountains of
Sri Lanka, with their networks steadily shrinking.

Another view is that Rakshasas are or were homosapiens who, like the Sikhs, follow a certain religious way (Vyam Raksham = aggression and protection of spiritual life) as opposed to a more secular approach like Yakshas (Vyam Yaksham = enjoyment and pleasure ignoring spiritual pursuits) -- distinct from the normal or middle path Vedic people and even Nagas (snake worshippers) follow. There were several other religious groups, for example the Dasas ("service and submission," like Divodasa and Sudas, who are called Aryan [Iranian, warrior, or noble] emperors, heroes of the Rigveda) whose religious beliefs were different.
Many times entire tribes or localities were painted with names. As
Vedic religion slowly triumphed over other ways or paths, they were assimilated. Aggressive
brahmins started calling
underdeveloped ("savage") tribes by the names of their past opponents.
Rakshasas (who were originally all
brahmins) was a misused term, as was
Dasyu (the priests of
Dasas), which came to mean savage.
Famous RakshasasRavana, the most famous
Rakshasa in ancient India, ruled from the
Trikuta Mountains (
Adam's Peak) in
Sri Lanka with climatic conditions similar to the Himalayas. He rose to the status of an emperor who exerted direct control from
Sri Lanka north to the south of the
Vindhya ranges in India, and indirectly over the kingdoms beyond.
Ghatotkacha was a
Rakshasa born to the
Pandava male
Bhima and the
Rakshasa female
Hidimbi.
Rakshasa Ghatotkacha's kingdom was in the Himalayas between
Gangotri and
Kailasa. The forefathers of
Ravana also lived there alongside the
Yakshas. The
Yaksha king
Vaisravana was the elder brother of the
Rakshasa king
Ravana.
Ravana had many sons with
Gandharva wives. The epics Mahabharata and Ramayana and many of the
Puranas attest that
Rakshasas,
Yakshas, and
Gandharvas were related by inter-marriage.
Famous
Rakshasa kingdoms in India were the

NagasNagas (Reptilians or snakes) were a group of people spread throughout India during the period of the epic Mahabharata. The demi-god tribe called the
Suparnas (to which the
Garuda belonged) were arch-rivals of the
Nagas. However,
Kashmir seems to be the original abode of all
Naga tribes. Places like
AnantNAG attests to this theory.
The
Naga race was almost exterminated by
Janamejaya, the
Kuru king in
Arjuna's line who conducted the massacre of
Nagas at Takshashila. This massacre was stopped by
Astika, a
brahmin whose mother was a
Naga (Vasuki's sister Jaratkaru).

SuparnasThe
Suparnas (a.k.a.
Garudas) were probably the
falcon-worshipping or falcon-rearing
Iranians who conquered the
Naga territories of Northwest India. They could also be the
Dragon- worshipping
Chinese people. They were arch-rivals of the
Nagas.
Garuda was a famous
Suparna. They were famous for the ability to fly without using aircraft. Some of the literature suggests that they had wings (or powerpacks) like
angels. Others consider them birds like hawks or eagles. And some think they were a race of intelligent
Dragons in the family of dinosaurs, which became extinct at the dawn of human civilization. Yet another view suggests that
Nagas and
Garudas were two rival factions of the same tribe. The Mahabharata also supports this view since it describes the two races as originating from two mothers who were sisters.
Vanaras
Vanaras were a tribe who dwelled within dense forests. During the time of the Ramayana, the central part of the Indian Peninans was covered by a dense jungle named
Dandaka Forest. Most of the
Vanaras lived there.
Kishkindha was their stronghold, holding sway over all of the
Vanara tribes spread across the Indian subcontinent. It was situated in this forest, located near the Tungabhadra river in the state of Karnataka. Some literature describes them as monkeys, some as apes.
References
Mahabharata of Krishna Dwaipayana Vyasa
Mahabhagavata Purana of Krishna Dwaipayana Vyasa
Ramayana of Valmiki Text: Wisdom Quarterly Wikipedia edit (wikipedia.org/answers.com)