1. Sangam (Cankam) Period
350 BC to 300 AD (roughly)
early chola period.
Assemblies (Academies) of Tamil scholars and poets that, according to traditional Tamil accounts, occurred in the remote past
originally known as kooṭal or gathering, which was also a name for Madurai

2. Three assemblies are described in the legends
Sangam Sangam Sangam 3
held in cities since taken by the sea.
Often considered fictitious and ahistorical.
Some like Kamil Svelebil find some truth in them.
held during the 5th century
BC in the present-day city of
Madurai

3. The word sangam has its mention in the sense of an
'academy' in several Tamil literary works like
Legend has it that Nammazwar's Thiruvaimozhi was
approved in an assembly of 300 poets.
Tevaram
Thiruvilayadal puranam
Periyapuranam
Irayanar Ahaporul

4. Tevaram (the first seven volumes of the Tirumurai, the twelve-volume collection of Tamil Śaiva devotional poetry, dedicated to the works of the three most prominent Tamil poets of 7th century, the Nayanars - Sambandar, Tirunavukkarasar and Sundarar)
Thiruvilayadal puranam (64 sacred sports of Siva written by Poet Paranjothi Munivar in early 1600s).

5. Periyapuranam (a Tamil poetic account depicting the legendary lives of the sixty-three Nayanars, the canonical poets of Tamil Shaivism. It was compiled during the 12th century by Sekkizhar. It provides evidence of trade with West Asia[1] The Periya Puranam is part of the corpus of Shaiva canonical works).
Irayanar Ahaporul ("Iraiyanar's treatise on the love-theme, called 'The study of stolen love'" (Tamil: களவியல் என்ற இறையனார் அகப்பொருள்) is an early mediaeval work on Tamil poetics, specifically, on the literary conventions associated with the akam tradition of Tamil love poetry. The date of the work is uncertain, but it is generally taken to have been composed between the fifth and eighth centuries.)

6. The earliest express references to the academies are found in the songs of Appar and Sampandar, Shaivite poets who lived in the 7th century

7. The first full account of the legend is found in a commentary to the Iraiyanar Akapporul by Nakkīrar (c. seventh/eighth century CE). He describes the three Sangams in detail

8. The first Sangam (mutaṟcaṅkam)mudharchangam is described as having been held at "the Madurai which was submerged by the sea", lasted a total of 4400 years, and had 549 members, which supposedly included some gods of the Hindu pantheon such as Siva, Kubera and Murugan. A total of 4449 poets are described as having composed songs for this Sangam. There were 89 Pandiya kings starting from Kaysina valudi to Kadungon were decedents and rulers of that period. The grammar followed in the first sangam was agattiyam. The poems composed were Paripaadal, mudunarai, mudukurugu, kalariyavirai. If credence is given to the commentary of Irayanar Ahapporul, the beginning of sangam should be placed somewhere in 9000 B.C

9. The second Sangam (iṭaicaṅkam) Idaichangam was convened in Kapatapuram
The second Sangam (iṭaicaṅkam) Idaichangam was convened in Kapatapuram. This Sangam lasted for 3700 years and had 59 members, with 3700 poets participating. There were 59 Pandiya kings starting from Vendercceliyan to Mudattirumaran were decedents and rulers of that period.This city was also submerged in sea. Ramayana and Arthasastra of Kautalya corroborates the existence of a city named kavatapuram

10. The third Sangam (kaṭaicaṅkam)kadaichangam was purportedly located in the current city of Madurai and lasted for 1850 years. There were 49 Pandiya kings starting from Mudattirumaran (who came away from Kabadapuram to present Madurai) to Ukkirapperu valudi were decedents and rulers of that period.[15] The academy had 49 members, and 449 poets are described as having participated in the Sangam.[16] The grammars followed were agattiyam and tholkappiyam. The poems composed were Kurunthogai,Netunthogai, kurunthogai nanooru, narrinai nanooru, purananooru, aingurunooru,padirrupaatu, kali,paripaadal,kuttu,vari,sirrisai and perisai

11. Late legends say that the third Sangam was held on the banks of the sacred Pond of Golden Lotuses in Madurai

12. Much of the early Tamil Literature is ascribed to the Sangams.
Legends of the Sangams played a significant role in
inspiring political, social, and literary movements in
Tamil Nadu in the early 20th century.