Gajabahu synchronism

Gajabahu synchronism is the chronological device used by historians to help date early Tamil history. The synchronism, first propounded by V. Kanakasabhai Pillai in 1904 in his The Tamils Eighteen Hundred Years ago, was adopted by some scholars of the time to date Tamil literature. Kamil Zvelebil, even while acknowledging the fragility of the synchronism, called it the "sheet anchor" of the dating of Tamil literature. The synchronism however, involves numerous conjectures and has been dismissed by Gananath Obeyesekere in his The Cult of the Goddess Pattini (1984) as ahistorical and invalid.

From a mention in the Silappatikaram, the Sinhalese king of Lanka, Gajabahu is taken to be a contemporary of the Chera king Senguttuvan. The genuineness of Gajabahu synchronism as an instrument to date early Tamil literature is accepted by most scholars today.

In the Silappatikaram, there is reference to a certain Kayavaku, the king of Sri Lanka. He is said to have attended the coronation of the Chera king Senguttuvan.

The 30th Canto, 160, in translation, reads -

The monarch of the world circumambulated the shrine thrice and stood there proferring his respects. In front of him the Arya kings released from prison, kings removed from central jail, the Kongu ruler of Kudagu, the king of Malva and Kayavaku, the king of sea-girt Ceylon, prayed reverently to the deity thus...

Kayavaku here, despite some disagreement has been conjectured to mean Gajabahu. The Silappatikaram, therefore is read to imply that, Gajabahu was a contemporary of the Chera king Senguttuvan, the protagonist of the epic. Sri Lankan history, however records the reign of two Gajabahus. According to the Mahavamsa, Gajabahu I reigned between 113 - 134 CE, while Gajabahu II reigned in the 12th century CE.

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