About Thevar History
Mukkulathor Means Three clans (Kallar, Maravar and Agamudayar) Combinedly called as Thevar or Devar.
Kallars are descendent lines of Cholars.
Maravars are decendent lines of Pandiyans.
Agamudaiyars are decendent lines of Cherars.
These three siblings are use the common name Thevar with their names known from ancient epigraphy.
Usually Mukkulathor people will ask for surnames and name of ancestral village when they encounter another Mukkulathor. (Purpose - Well we want to know how we are related to one another)

Mukkulathor -
Mukkulathors are among the first tribes to live in ancient Tamil land. On other words, Mukkulathors are native tamils. This is confirmed through literature and also genetic research. The history of Mukkulathor people is well documented and any one can find references to these clans in literature and stone inscriptions.
According to the National Geographic Genome Project, The piramalai Kallars were among the first tribe to settle down in ancient Tamil Land. This was confirmed through studies by Dr.Spencer Wells.
One of the Mukkulathor caste member, Virumandi Andi Thevar, A system administrator from a small village close to Madurai (India), has been identified as one of the direct descendants of the first ever settlers in india, some 70,000 years ago ( Research was part of the "Genographic Project")
The Mukkulathors also believe that they are the entire same branch which later split to three different clans.