The Thomas of Cana copper plates (Malayalam: Knai Thoma Cheppedu), or Knanaya copper plates, dated variously between 345 C.E. and 811 C.E., are a lost set of copper-plate grants issued by the unidentified Chera/Perumal king of Kerala "Co-qua-rangon" to Syriac Christian merchants led by Knai Thoma (anglicized as Thomas of Cana) in the city of "Makotayar Pattinam" (present day Kodungallur), south India.[1][2][3][4][5] The royal charters were reportedly engraved in ”Malabar”, Chaldean and Arabic on both sides of two copper plates (joined by a ring).[1][4][5] Archbishop Francis Ros notes in his 1604 account M.S. ADD 9853 that the plates were taken to Portugal by the Franciscan Order.[6]
Scholar M.G.S. Narayanan tentatively identifies king “Co-qua-rangon” with king Rama Rajasekhara (Co-qua-rangon → Ko Kotai Iraman → Rajadhiraja Rama) of the 9th century Chera Empire.[7] [5]
The Knanaya or the people of Knai Thoma were historically associated with the southern portion of the Chera/Perumal headquarters Kodungallur until in 1524 they were dispersed from the city due to conflict between the Kingdom of Cochin and the Kingdom of Calicut. The plate was cherished by the Knanaya as evidence of their arrival in Kerala under the leadership of Knai Thoma as well as a notation of the historical, economic, and social rights bestowed upon them by the Chera Perumal.[8][9] The native Christian tradition places the arrival of Thomas of Cana in 345 C.E.[10]
Translations of the existing Kollam Syrian Plates of the 9th century made by the Syrian Christian priest Ittimani in 1601 as well as the French Indologist Abraham Anquetil Duperron in 1758 both note that one of the plates mentioned a brief of the arrival of Knai Thoma.[11][12] It is believed that this was a notation of the previous rights bestowed upon the Christians by Cheraman Perumal.[12] The contemporary set however does not mention this paragraph and is believed to be incomplete or a later inscription. Scholar of Early Christian history István Percvel theorizes that at one time the Kollam Syrian plates and the Thomas of Cana plates were re-engraved together as a single unified grant.[11]