History of Tamil language is very rich and dates back to around the 2nd century BCE and is considered amongst the longest existing classical languages throughout the world. Tamil is a Dravidian language which is spoken primarily by Tamil people in India. Tamil language is perhaps the sole language of modern India which is still recognizable with its conventional past and comprises of one of the richest literatures in the globe. Tamil includes the most ancient non-Sanskrit Indian literature amongst all other Indian languages.

Proto-Dravidian Language
Tamil is a Dravidian language which comes down from Proto-Dravidian. It is believed that Proto-Dravidian language was used around the 3rd millennium BC, probably in the lower Godavari river basin region of peninsular India. Historical evidence recommends that the culture related with the Neolithic complexes of South India mainly spoke Proto-Dravidian. Proto-South Dravidian appears as the next stage in the recreated proto-history of Tamil language. Evidence suggests that Proto-South Dravidian language was used during the middle of the 2nd millennium BC. Proto-Dravidian language was also spoken in parts of Northern India and some of the evolved Dravidian languages of the north include Gondi, Oroan, Brahui, Khurukh, Gadba, Malta, Konda, Kuvi, Parji, Gondi, Ku, Naiki and Kolami. Eventually, proto-Tamil evolved during the 3rd century BC. The oldest epigraphic attestations of Tamil are usually considered to have been written after it.

According to experts and scholars, the history of Tamil language can be classified into 3 distinct periods, Ancient History of Tamil Language (300 BCE-700 CE), Medieval History of Tamil Language (700-1600) and Contemporary History of Tamil Language (1600-Present).

Ancient History of Tamil Language
The oldest accounts in ancient Tamil language are short inscriptions on pottery and in caves that dates back from around 2nd century BCE. The inscriptions are composed in a deviation of the Brahmi script known as Tamil Brahmi. Tolkappiyam, the earliest text in ancient Tamil language, is an initial work on grammar and poetics of Tamil. The earliest layers could be traced back to the 1st century BC. Along with the Tolkappiyam, numerous other literary works from the ancient era has also been recovered. The most prominent being the Sangam literature which is a corpus of 2,381 poems. The poems belong to the period between 1st and 5th centuries and thus the Sangam literature is the earliest available work of secular literature in India. Manimekalai and Cilappatikaram are 2 long epics which are amongst the other renowned literary works that belong to the ancient Tamil language. Moreover, numerous didactic and ethical texts, written between the 5th and 8th centuries, have also survived.

Ancient Tamil contained several traits of Proto-Dravidian, like the syllable structure, the inventory of consonants and various grammatical characteristics. There was the absence of a discrete present tense and similar to Proto-Dravidian, ancient Tamil contained only 2 tenses, the past and the non-past. Ancient Tamil verbs also contained a distinct negative conjugation. Nouns could take pronominal suffixes like verbs to express ideas. Even though there are significant grammatical and syntactical changes between different classifications of Tamil language, but it demonstrates grammatical continuity.

Medieval History of Tamil Language
Medieval history of Tamil language is considered to have begun from around the 8th century and the evolution from ancient Tamil to medieval Tamil is described by numerous grammatical and phonological changes. The phonological changes were marked by the practical disappearance of the Aytam, an old phoneme; the transformation of the alveolar plosive into a rhotic; and the coalescence of the alveolar and dental nasals. In grammar, the most significant change was the advent of the present tense. The present tense developed out of the verb Kil, which meant "to befall" or "to be possible". In ancient Tamil language, this verb was utilised as an aspect indicator to specify that an action was micro-durative, non-sustained or non-lasting, generally in amalgamation with a time marker such as n. In medieval Tamil, this practice progressed into a present tense marker- kinr- which pooled the old facet and time markers.

Medieval Tamil language also witnessed the increasing use of Sanskrit in Tamil. Since the reign of the Pallava dynasty, several Sanskrit loan words appeared in Tamil language, particularly related to philosophical, religious and political concepts. Tamil grammar was influenced by Sanskrit with the augmented use of cases and in declined nouns becoming adjuncts of verbs and phonology. The Tamil script also underwent transformation during this period. It evolved into Tamil Brahmi and Vatteluttu which were the major scripts utilised in ancient Tamil inscriptions. Later Vatteluttu was replaced during the 8th century, as the Pallavas started to use a new script which was derived from the Pallava Grantha script and was used to write Sanskrit.

Medieval Tamil language is demonstrated in several of inscriptions and in a noteworthy body of religious and secular literary works. These consist of the religious poems and songs of the Bhakthi poets, like Nalayira Tivya Pirapantam on Vaishnavism and the poems of Tevaram on Shaivism. These also include adaptations of religious epics like the tale of 63 shaivite devotees known as Periyapuranam and the 12th century Tamil Ramayana written by Kamban. A 12th century grammar known as Nannul which was the standard grammar of literary Tamil and Iraiyanar Akapporul, an early thesis on love poetics, are also from Medieval Tamil literature.

Contemporary History of Tamil Language
The Nannul is still considered as the standard normative grammar for modern Tamil literature, which is based on medieval Tamil of the 13th century instead of contemporary Tamil. Colloquial spoken Tamil language portrays several of changes. The negative conjugation of verbs has fallen out of use in contemporary Tamil rather negation is expressed either syntactically or morphologically. Modern verbal Tamil also illustrates numerous sound changes, particularly a propensity to lower high vowels in initial and medial positions and the fading of vowels between plosives and between a plosive and rhotic.

Both written and spoken Tamil were also influenced by European languages like the use of punctuation and the use of consonant clusters, which were conceptually not allowed in medieval Tamil language. The syntax of written Tamil has also converted with the emergence of new aspectual auxiliaries and more intricate sentence structures, along with the introduction of a further rigid word order which is similar to the syntactic argument structure of English.

Concurrently, a strain of linguistic purism evolved in the early 20th century, resulting in the Pure Tamil Movement which demanded the eradication of all influences of Sanskrit and other foreign elements from Tamil. This resulted in the removal of numerous Sanskrit loan words that were replaced by Tamil counterparts.