. Logan says that the नम्बूतिरिस् were the batch of Aryans that settled down in केरल after the नैर्स् . The historians like शङ्कुण्णि मेनोन् and others have stated that the नम्बूतिरिस् had come to केरल from the banks of the rivers गोदावरी , नर्मदा and कावेरी . Famous historians have inferred that the progress of the Aryans to the south took place between 1000 and 325 B.C. But Thomas Fawlks thinks that there were नम्बूतिरि priests and hermits in South India, during the time of बुद्ध . N.K. Datta, the author of the book "Aryanisation of India", is of opinion that during the time of the invasion of Alexander, the Aryans had spread all over India and चेय्लोन् . Thus historians have not yet come to an agreement as to the correct period of the exodus of the Aryans to the south. Anyhow in the Geography of Ptolemy mention is made that half a degree east to Taibis there was a place called ब्रह्मगार . It may be assumed that ब्रह्मगार may be ब्रह्मागार (settlement of Brahmins). It has been decided definitely that the period of Ptolemy was A.D. 2nd century, and in that case the Brahmins must have settled in the south before that period

Though the period of the 'Saṅgha poets and their works' has been assessed differently by different scholars, the majority have fixed it as the first few centuries of A.D. In these सङ्घ poems the gods of the Aryans are praised. The gods सूर्य ( थे सुन् ), चन्द्र ( थे मोओन् ), वरुण (god of water), बलदेव ( श्री कृष्ण 's elder brother) and विष्णु (Supreme God) are specially mentioned in 'Cilappadikāra'. The सङ्घ work 'Puranānūru' is an encomium to the purity of the वेदस् and अग्निहोत्र ब्रह्मिन्स् (Brahmins who maintain the holy fire by burnt offering). In those days the King carried on the administration of the country with the advice of ब्रह्मिन्स् . Economics, Grammar and law were taught in royal palaces. पञ्चाक्षर and such other spells, reading of the scriptures, Aryan ways of marriage, Recitations of पुराणिच् stories etc. were prevalent in those days. मणिमेखला is stated to have reached the capital of the चेर King and learned वेदस् and साङ्ख्य doctrines (one of the six systems of Indian Philosophy dealing with evolution) from the prominent teachers here. The diction of both the works 'Cilappadikāra' and 'Maṇimekhalā' is, to a certain extent, indebted to सन्स्क्रित् . Many of the सन्स्क्रित् poetic traditions are used in these poems. When these proofs are taken into account, it is not wrong to presume that in the period from 1st century to 5th century A.D. Aryan civilization prevailed in south India. If, during this period, Aryan civilization had taken root to such an extent in south India, the advent of the Aryans to south India must have taken place at least two or three centuries prior to this period.

The नम्बूतिरिस् of केरल are called मलयाल ब्रह्मिन्स् . Between them and the Brahmins of other countries there are differences in manners and customs. They are given below:--

The ब्रह्मिन्स् of other parts of इन्दिअ do not perform अग्निहोत्र rites (maintaining the holy fire by burnt offering) so elaborately as the मलयाल ब्रह्मिन्स् .

Among the sixteen purificatory rites, अग्निस्वीकार (or taking up of sacrificial fire) is an important item in मलबर् . From Vedic period अग्नि (Fire) had become a prominent God. Most of the verses in ऋग्वेद are concerned with fire. The attachment of the ब्रह्मिन्स् of केरल to fire shows their antiquity.

Much importance is attached to the learning of scriptures and priest-hood in केरल . There were 18 मठस् and residential institutions in केरल for giving religious education.

The peculiar type of recitation of the वेदस् of the मलयाल ब्रह्मिन्स् and the accompanying gestures of their hands and the movements of the head at the time of recitation are considered by them to be ancient. Even today certain sounds are produced by them in the Vedic way. (For instance Samrāl--Samrāṭ • Vaṣar--Vasaṭ • Īḍe--Īle etc.) .

In Malabar there is a customary atonement or expiation called व्रात्यस्तोम for those ब्रह्मिन् boys who had not undergone investiture with the sacred thread within the stipulated time. This shows the stress laid on the need of religious education.

The custom that all the male members of the family except the family chief should be engaged in ' स्नातकवृत्ति ' (should remain celibates even after education) is prevalent only in Malabar.

Much importance is attached to evening worship in केरल . At that time the वेदिच् gods are not hailed. But ब्रह्मिन्स् of other places do not seem to attach so much importance to this practice.

The ब्रह्मिन्स् outside केरल repeat the mantras uttered by the priest and perform the functions, at the time of meditation and worship. But in केरल for meditation and worship with or without incantations a priest is not necessary. This indicates the practice in vogue during वेदिच् period before the priestly class became predominant.

The नम्बूतिरिस् have recognized only three वेदस् .

The केरल ब्रह्मिन्स् wear only one sacred thread. The नम्बूतिरिस् became predominant in केरल and began to have a hand in the various spheres of activities. Thus the अर्यन् civilization shook the customary faith and religion of केरल from top to bottom and the अर्यन् religion hoisted its flag of victory here. अर्यन् literature also found its way into केरल . The authors and scholars in केरल began to imitate it. The नम्बूतिरिस् erected temples in केरल with the help of local chieftains. The sounds of alphabets, sentence pattern, grammar, poetic tradition etc. of मलयालम् language underwent a thorough change. सन्स्क्रित् education spread far and wide. They spread अर्यन् civilization through 'Kūttu and Kūṭiyāṭṭam (Narration of mythological stories with gestures etc. and collective dance) Pāṭhaka and सङ्घक्कलि (Musical lectures and dramatic performances), in connection with festivals in the temples. They absorbed many of the customs and manners of केरल . The नम्बूतिरिस् who had adopted priest-hood as their career had amassed wealth and landed property in the capacities of priests and authorities of the temples. Some of them became Kings ( ए।ग्। King of इडप्पल्ल्य् , King of चम्पकश्शेरि etc.). They kept up the contact with the people of the locality by means of morganatic marriages and made their positions secure. Thus these people, though a small minority, were able to hold sway over the people of केरल for a long time.