[2][3] Beginning in 1517, he served as the crown's official cartographer and was given exclusive rights to "constructing and correcting... nautical compasses.

[5] In 1524, Homem was involved in preliminary negotiations on behalf of the Portuguese crown as an expert witness at the Conferences of Badajoz-Elvas, which aimed to settle a dispute with Castile for the Molucca Islands.

[1][8] A letter written by Lopo Homem alluding to the board quarrels over the claims of the two kings on exploration rights remains in the Torre do Tombo.

[11][1] Because of its "luxurious" work and detail, it is thought that King Manuel I of Portugal commissioned it as a state gift for Francis I of France.

[2] In the mid-16th century, Homem criticized inaccurate maps, both for "damag[ing] the geopolitical interests of the Crown... [which] could cause significant territorial losses" and for increasing the probability of shipwrecks and sailor deaths.