2. What did Mendonca record during his voyage around Illa do magna? (the North Island of New Zealand)

Mendonça’s fleet mapped the eastern coastline of Australia and most of the North Island of New Zealand long before other modern European explorers officially recorded their discoveries. The map is included in the Vallard Atlas, part of the Dieppe Portulan map series stored in the Huntington Library, San Marino, California, USA.

The Vallard Atlas is a remarkable collection of maps that depict the extensive Portuguese voyages of the time with astonishing detail. The maps are drawn in sumptuous colour, showcasing the artistry and precision of the cartographers. This level of detail and beauty not only highlights the navigational achievements of the Portuguese but also serves as a testament to their exploration prowess during that era. 

The Vallard Atlas 1547 comprising 15 maps is of greatest interest in the 22 Dieppe Maps series. First, the reference to Jave La Grande or Terra Java substantially matches the eastern coastline of Australia. Second, there are over 120 Portuguese place names on Jave La Grande showing the original information was produced by Portuguese. Third, there is a close association of the island Illa do magna to the North Island of New Zealand.

One of the maps in the Vallard Atlas shows "Illa do Magna," which translates to "Great Island." This island also appears on three later Dieppe maps, reinforcing its recognition among Portuguese explorers. A strong reference of Portuguese discovery of New Zealand.

Note: The North Island of New Zealand or “Illa do magna” is not completely mapped. Mendonca’s first contact with New Zealand was in Taranaki where he chose to sail south through Cook Strait then headed north up the eastern coast of the North Island. Once he reached Auckland, he headed north to catch the monsoon winds for his journey back to India with the result Northland is missing from the portulan map.

The following blogs examine how we can establish credibility for the revelations in the Vallard map of Illa do Magna and continues the topic of Pre-Abel Tasman exploration of New Zealand.

Your next read in the series: 3. What do we know about Mendonca’s voyage of exploration around the North Island of New Zealand?