Historical reference to Tamils or Pandyas occurs in the work inscriptions of Megasthenes. Megasthenes was a Greek historian and diplomat who served as an ambassador of the Seleucid Empire to the court of the Mauryan Emperor Chandragupta Maurya in the 4th century BCE.

1. Introduction:
- The historical references to Tamils or Pandyas can be traced back to the works of Megasthenes, a Greek historian and diplomat.

2. Megasthenes and his works:
- Megasthenes visited the court of Chandragupta Maurya and wrote a detailed account of his observations and experiences in a book called "Indica".
- "Indica" is an invaluable source of information about ancient India, its geography, society, and political structure.

3. Tamil and Pandya references in Megasthenes' works:
- Megasthenes' writings mention the existence of a powerful Tamil kingdom known as the Pandya kingdom.
- The Pandyas were one of the four major Tamil dynasties that ruled over parts of present-day Tamil Nadu and Kerala in ancient India.
- Megasthenes' references to the Pandyas provide valuable insights into the political and cultural landscape of ancient Tamil Nadu.

4. Significance of Megasthenes' works:
- Megasthenes' works are considered significant because they provide an external perspective on ancient India, corroborating and supplementing the existing indigenous sources.
- His writings help in understanding the political and social structures of ancient Tamil Nadu, including the existence of powerful kingdoms like the Pandyas.

In conclusion, the first historical reference to Tamils or Pandyas can be found in the works of Megasthenes, a Greek historian and diplomat who visited the court of Chandragupta Maurya in the 4th century BCE. His writings provide valuable insights into the existence and significance of the Pandya kingdom, one of the major Tamil dynasties in ancient India. These works help in understanding the political and cultural landscape of ancient Tamil Nadu and are of great historical significance.