The Laguna Copperplate Inscription is the earliest known written document found in the Philippines. The plate was found in 1989 by a laborer near the mouth of the Lumbang River in Barangay Wawa, Lumban, Laguna. The inscription on the plate was first deciphered by Dutch anthropologist Antoon Postma.
The discovery of the plate is cited as evidence of cultural links between the Classical Tagalog people and the various contemporary Asian civilizations, most notably the Javanese Medang Kingdom, the Srivijaya Empire, and the Middle kingdoms of India.
The inscription is on a thin copper plate measuring less than 20 × 30 cm (8 × 12 inches) in size with words directly embossed onto the plate. It differs in manufacture from Javanese scrolls of the period, which had the words inscribed onto a heated, softened scroll of metal.
Inscribed on it is year 822 of the Saka Era, the month of Waisaka, and the fourth day of the waning moon, which corresponds to Monday, 21 April 900 CE in the Proleptic Gregorian calendar. The writing system used is the Kawi Script, while the language is a variety of Old Malay, and contains numerous loanwords from Sanskrit and a few non-Malay vocabulary elements whose origin may be Old Javanese. Some contend it is between Old Tagalog and Old Javanese. The document states that it releases its bearers, the children of Namwaran, from a debt in gold amounting to 1 kati and 8 suwarnas (865 grams).
Dutch anthropologist and Hanunó’o script expert Antoon Postma has concluded that the document also mentions the places of Tondo (Tundun); Paila (Pailah), now an enclave of Barangay San Lorenzo, Norzagaray; Binuangan (Binwangan), now part of Obando; and Pulilan (Puliran); and Mdaŋ (the Javanese Kingdom of Medang), in present-day Indonesia. The exact locations of Pailah and Puliran are debatable as these could refer to the present-day town of Pila and the southeastern part of Laguna de Bay (a large freshwater lake southeast of Metro Manila) that was previously known as Puliran—both close to where the plate was found.
The reference of “Namwaran” may also have the connotation for nawara, a Visayan term used in reverence for the dead. In old Visayan custom, the name of dead persons were not used in conversation out of respect. The word Binwangan in modern Waray means “river mouth”, while Puliran would mean to roll from hills to a flatland, a topographic feature of the present-day town of Lumban.