The Vanniyar are a community or jāti found in Southern India.
Several etymologyies for Vanniyar have been suggested, including the Sanskrit vahni ("fire"), the Dravidian val ("strength"), or the Sanskrit or Pali vana ("forest"). Another theory is that they are named for the vanni tree which they held sacred.
In the 19th century the Vanniyar held a low position in both Lower Burma and in South India.[page needed] For example, Dharma Kumar refers to several early 19th century authors who describe the Palli in South India as being higher than untouchables,[page needed] while Michael Adas says that in Burma the Palli were "socially better off" than the untouchable castes but were "economically equally exploited and deprived".
Researcher Lloyd I. Rudolph notes that as early as 1833, the Palli filed a claim in Pondicherry to prove they were not a low caste, and in preparation for the 1871 Indian census they petitioned to be recognised as being of the Kshatriya (warrior) varna of Hindu society. By 1931, due to their successful politicking, the term Palli was removed from the Madras census, with the term Vanniya Kula Kshatriya appearing instead.
The Vanniyar formed a number of caste organisations, with the Vanniyakula Kshatriya Maha Sangam appearing in Chennai in 1888.
Traditionally most Vanniyars are agricultural labourers. Increasingly however, they are benefiting from political influence and organization and they now own 50% of the lands of the traditional landowners. The Vanniyars were classified as the Most Backward Caste after successful agitations in the 1980s. Vanniyars are the single largest community in Tamil Nadu.
Many castes today claim descent from Malayaman Dennis B. McGilvray in his book "Crucible of conflict" states "Malayaman is just a section/title of the udaiyar caste in south arcot today, but Burton Stein also finds the title in a thirteenth-century inscription identifying Vanniyar subcastes of south arcot in the left-right caste classification typical of the chola empire". Again Malayaman is mentioned as Vanniyar by Padmanathan in his book 'The Kingdom of Jafna'. 
Noboru Karashima believes that epigraphic evidence proves that leaders of the Kadava dynasty were Vanniyar by caste. He says "We have three more inscriptions of Kulottungachola Kadavarayan, which are found in Viriddhachalam (SII, vii-150: SA, 1148), Srimushnam (ARE, 1916-232: 1152), and Tirunarunkondai (SITI-74:SA, 1156). In the first two he is described as a Palli". Karashima also refers to other Kadava chiefs, being Kachchiyarayan, Cholakon and Nilagangaraiyan.
Karashima says "From the above it is clear that the Kadava chiefs, who were Pallis (Vanniyars) by jati and had estabilished their power in Gadilam River area."
Sambuvarayars were chieftains who belong to the Palli(Vanniyar) caste..The Sambuvarayars ruled mainly northern districts. The first chieftain identified is Omainthan Munnutruvan Palliyana karanamanikam.In this"South Indian Inscriptions Vol.7,Number 500" inscription this chieftain is mentioned as a Palli. He is considered to be the ancestor of the Sengeni Sambuvarayas. He is identified during Sundara Chola’s rule.After him the Sambuvarayas started gaining power and soon attained the position of feudatory rulers. Madura Vijayam, a Sanskrit poetical work by Gangamma mahadevi about vijayanagar prince, Kumara Kampanna Udayar or Kumara Kampanna II, the second son of Bukka Raya I quotes thus "Bukka advised his son to march against the Sambuvaraya chieftain who "is the leader of the Vanniyar and he is preparing for war.  If you subdue the Vanniyar ruler, it would be easy for you to break the power of the Muslims at Madura". From the above mentioned it is clear that Sambuvarayars are Vanniyars
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