From his Malay-Indonesia travels, he wrote a book on Asian trade, the
Suma Oriental que trata do Mar Roxo até aos Chins (An Account of the East, from the Red Sea to China). He wrote the book in Malacca and India between 1512 and 1515, completing it before the death of
Afonso de Albuquerque in December 1515. It was the first comprehensive and reliable account of Asia to the east of India, a region that was almost unknown to Europe at the time. Among its many accomplishments, it contained the first European descriptions of the
Malay Archipelago and the
Spice Islands. The historical account of Malacca is the earliest known and contains much information not found anywhere else. Pires was also the first to use the name Japan, spelling it as
Jampon. The details and accuracy of his descriptions of Sumatra and Java are "remarkable" and were not surpassed for a "couple centuries". It remains one of the most important resources for the study of
Islam in Indonesia. The
Suma Oriental is a compilation of a wide variety of information: historical, geographical, ethnographic, botanical, economic, commercial, etc., including coins, weights and measures. Pires was careful to investigate the accuracy of the information collected from merchants, sailors and others with whom he had contact. It shows him to be a discriminating observer, in spite of his tangled prose. "His style is far from clear," his modern editor has noted, "and no doubt it often becomes more confused, owing to the transcriber's mistakes." The book, couched as a report to
Manuel of Portugal, and perhaps fulfilling a commission undertaken before he left
Lisbon, is regarded as one of the most conscientious first-hand resources for the study of the geography and trade of the Indies at that time. Although it cannot be regarded as completely free of inaccuracies in its detail, it is remarkably consistent with evidence of the time and makes no fundamentally erroneous statements about the area. Its contemporary rival as a source was only the better-known book by
Duarte Barbosa. The
Suma Oriental was unpublished and presumed lost until 1944 when a manuscript copy was discovered in a Paris archive. Four letters written by Pires survive, and there are a scattering of references to him by contemporaries, including a letter from Albuquerque to the King, 30 November 1513. == 1516 embassy to China ==