Career
On 3 April 1529 he sailed two ships to the island of Sumatra with the aim of breaking the Portuguese spice trade monopoly. They reached the western coast of Sumatra at the end of October, but were unable to buy the quantity of spices wanted. The surviving crew members voted to return to France and, on 22 January 1530, they set out.
Both ships returned safely to France.
In 1531 Pierre Crignon, the chief pilot on the Sumatra expedition, published a collection of Jean’s poetry. Although Jean was well known as a cartographer, none of his maps has survived.
The expedition was accompanied by "Jean Sasi, le grand Peintre". Upon their return they triggered the development of the Dieppe maps, influencing the work of Dieppe cartographers, such as Jean Rotz.