Sourashtrians are mostly silk weavers and silk thread merchants, originated in the Saurashtra region (present day Gujarat, and parts of Maharashtra) in Northern India and later settled in Madurai and surrounding regions of Tamilnadu, few centuries ago.
The origin is certain, and research has proved the current day Sourashtra spoken by us is a modern form of pre-Gujarati spoken thousands of years ago. "
Their home language (Sourashtra language) is still a modern form of the old Saurashtri or Pre-Gujarati as it was over a thousand years ago, which was the language they brought with them through Maharashtra, Karnataka and Andhra pradesh to Tamilnadu. This language preserves, naturally enough many archaic features of Gujarati and at the same time shows influence of the sister Aryan languages of Konkani and Marathi and of Dravidian Telugu, kannada besides of course Tamil which has now virtually become the second mother tongue of the Sourashtrians...." says Suneetkumar Chatterjee a famous linguist.
But the time period when they migrated from Saurashtra region to south is still uncertain.
The first theory is that, during the times when the infamous Ghazani Mohammed invaded Northern India from Afghanistan, a few families might have migrated South to escape from the series of invasions.
Another assumption is a few families that came with the entourage of Shatrapathi Shivaji when he invaded south, might have stayed back to form their own community.
This is the most popular and widely accepted theory by historians. During the Vijayanagaram Empire rule in Northern India, the Nayakars ruled the South as part of the empire with Madurai as their capital. During that period a few families from the Saurashtra region were called into Madurai to be the "Royal Weavers" for the Nayakars. This would explain very high concentration of Sourashtrians still today around the Thirumalai Nayakar Mahal, the Nayakar's Palace. Since Sourashtrians are Silk Weavers by profession it would also disprove the theory that they came with Shivaji.
Later Sourashtrians settled in Madurai, spread around to Trichy, Salem, Kumbakonam and other surrounding areas as the population grew, but still managed to keep their unique language, and culture intact. Current day Sourashtrians, refer themselves as Tamilians as their identities and still speak Sourashtra at home. An estimated half a million Sourashtrians are living now mostly in Tamilnadu and a few are spread around all over the world.