Dr.P.K.Gopalakrishnan is of the view that Nairs were a transitioned group of people from among the Keralites. According to him no historical evidences are available about the existence of Nairs before 8th century AD. Evidence of their migration to Kerala during or around 8th century AD was also not available.

“Ayar” who resided in Lothal area (Gujarat, South Rajasthan) were a strong people under the leadership of Lord Krishna as mentioned in Rigveda. Kesari Balakrishna Pillai quoting Max Muller says that Nagas inhabited in between Lothal and Sind where the river Sindhu (Indus) joins the sea. The union between the Nagas who excelled in agriculture and sailing and Ayars, experts in cattle farming and warfare resulted in the formation of Nair, a group of Kerala people. (Nagar + Ayar = Nayar)

Dr.P.K.Gopalakrishnan is of the view that the people of Kerala belonging to different groups, in due course of time might have become Nairs. The origin of Nair may be from Ayar, Idayar, Velalar or Maravar. Though Nairs were spread throughout Kerala, they are concentrated mainly in midlands. This is one of the reasons to believe that groups like Ayar and Idayar as a whole were become Nairs.

In the book ‘Aryan settlement in India’ it is stated that Aryans migrated to the interior of South India and their later generations came to be known as Nairs.

Some argue that during the period of Brahmin supremacy they selected groups of people from various communities and thus formed the nair community. The rulers gave the title “Nair” to their favorites.

Sri.Ilankulam Kunjan Pillai claims that Nairs were descendents of the suicide squad. Their origin was in the 11th century AD.

Sri.K.P.Padmanabha Menon, renowned historian is of the opinion that Nairs who were the rulers of Kerala in olden times were called “Nayaka” (one who leads) and this “Nayakar” later became Nair.

Sri.Pattom G.Ramachandran Nair is of the opinion that Nair may be a term cut short from ‘Nayanar’. In South India Buddhists and Jains were commonly known as ‘Nayanars”. Nayanar is the family title of some of the families in North Malabar and Tamil Nadu. The famous Kallyasseri family of North Malabar (family of former Chief Minister Sri.E.K.Nayanar) got this title from Kolathiri Rajah. The famous Shaivites of Dravidian country were later known as Nayanars. The word Nayanar means Nayakan (one who leads).

Kosambi opined that the Nair community originated from the tribal women of Kerala in the union with Brahmins.

The Encyclopedia published by the State Encyclopedic Department says that there are evidences to prove that Nairs were the protectors of Hinduism during the period of Shiva Bhakthi movement in Kerala.

“By the time the Brahmins arrived in Kerala, about the first millennium, the first known rules of Kerala, the Cheran, who were Nairs, already had an established kingdom there. Logan in his ‘Malabar Manual’ says that the Namboodiris respected Nairs as kings. Fahien, the Chinese traveller, who visited India in AD 1409 noted that “Nairs rank with kings”. They were owners and controllers of temples and enjoyed all the privileges of high - caste Hindus.” (Religions and Communities of India).

Kanippayoor Sankaran Namboodiriippad says that Nairs were the bodyguards of North Indian Brahmins who came to Kerala by sea from Sindh. (Nayanmarude Poorvaocharithram).

One recent theory proposed by Dr. Thundy is that Nairs are the descendants of the Newars of Nepal, who migrated to Kerala. There are two major facts to support this view. The first is the lighter complexion, and sharper features of Nairs. The second is the distinct pagoda-like architectural style of Nair Tharavaadus and Temples. Finally, there is the Marumakkathaayam system of inheritance. This system is a matrilineal system, which is also practiced by the Newars of Nepal. Southern Indian warrior class names like Naik, Naidu etc are closely connected to Kerala Nairs, even though the anthropological links are not yet established. (Wikipedia)

Most anthropologists are of the view that the Nair caste is an amalgamation of various warrior classes during the post-Sangam era, which is considered as the most politically unstable period in Kerala history. All the Cheras were Nairs and Kerala history is more or less connected to Nair caste. (Wikipedia)