During his tenure in these successive posts at the Cathedral of Rouen (1364-1377), Oresme spent a lot of time in Paris, especially, in the context of attending to the affairs of the University.
With the commencement of Oresme’s prolonged translating activities at the request of Charles V, he did reside continuously in Paris, as is shown to be true by letters dating from August 28 to November 11, 1372 sent by Charles to Rouen.
Oresme’s residency in Paris appears to have been extended by Charles to 1380, when Oresme began working on his translation of Aristotle’s Ethics in 1369, which appears to be completed in 1370.
On November 23, 1362, the year he became master of theology, Oresme was appointed canon of the Cathedral of Rouen.
At the time of this appointment, he was still teaching regularly at the University of Paris.
Beginning in 1356, during the captivity of his father, John II, in England, Charles acted as regent and from 1364 until 1380, King of France.
On November 2, 1359, Oresme became "secretaire du roi" and in the period following, it appears that he became chaplain and counsellor to the king.
Oresme's economic views are contained in "Commentary on the Ethics of Aristotle", of which the French version is dated 1370; "Commentary on the Politics and the Economics of Aristotle", French edition, 1371; and Treatise on Coins (De origine, natura, jure et mutationibus monetarum).
These three works were written in both Latin and French; and all of them, especially the last, stamp their author as the precursor of the science of political economy, and reveal his mastery of the French language.
There is a long tradition that says that Nicole Oresme was also the tutor to the dauphin (who later became Charles V), but this is not quite certain.