Giacomo Gastaldi (1500-1566) is considered the foremost Italian cartographer of the sixteenth century, alongside Paolo Forlani. His skills of compilation are comparable to those of Mercator and Ortelius, yet much less is known of his life than of his two contemporaries. Gastaldi was born in Villafranca, Piedmont, but had established himself in Venice by 1539. He originally worked as an engineer, but turned to mapmaking from the 1540s onward.

It was in Venice where he made his reputation as an engraver, geographer, and cosmographer; for example, he was asked to fresco maps of Asia and Africa in the Palace of the Doge, or the Council of Ten, Venice’s governmental body. He also frequently consulted on projects for the Savi sopra la Laguna, drawing maps for this body which oversaw the regulation of fresh and salt water around Venice. 

His contemporaries also recognized his skill, as he was named cosmographer to the Republic of Venice, was a member of the Accademia Veneziana, and was a major source for other geographers and mapmakers including Camocio, Bertelli, Cock, Luchini, and Ortelius. He even had his own distinct style of copper engraving that made him a pioneer in his day and makes his works iconic today.

Gastaldi enjoyed an especially productive relationship with Giovanni Battista Ramusio, Secretary of the Venetian Senate, who used Gastaldi's maps for his famous travel account collection, Navigationi et Viaggi. Gastaldi also tutored Ramusio's son in cosmography.