By the terms of the Treaty of Aix-la-Chapelle (1748), Louisbourg, which had been taken by the English in 1745 (see First Siege of Louisbourg), was to be returned back to France. Des Herbiers was appointed to sail from France at the head of the French forces which were to re-occupy Louisbourg, and, to become her new governor. Sailing from Rochefort in May, 1749, Des Herbiers and his entourage arrived at Louisbourg on June, 29th. He had with him approximately 2,000 returning French civilians and 1,000 soldiers.
Des Herbiers was a navy man. He had been raised by his uncle, a Rear Admiral in the French navy. He became a midshipman in 1719; and, indeed, his first assignment was aboard the Chameau. During his naval career, Des Herbiers was to sail to New France on a number of occasions, including some charting expeditions in and around Louisbourg.
The English commander, Peregrine Thomas Hopson, at Louisbourg, during the course of an official ceremony, handed the keys of the fortress over to Des Herbiers. As is often to be seen in the historical accounts, the English and the French, in the course of their official treatment of one another (it being the style and custom of the age), always dealt with one another with much courtesy and consideration. Hobson, had been somewhat let down by the English authorities in that he did not have sufficient transports to bring his people to the newly founded Halifax -- "No problem, Monsieur." As Des Herbiers might have been heard to say, "Our transports will be put at your disposal."
Des Herbiers, incidentally, was instrumental in "encouraging" the Acadians, through the offices of Le Loutre, to relocate to Ile Royale (Cape Breton) and Ile Saint-Jean (Prince Edward Island). ["... Ile Saint-Jean grew from 735 in 1749 to more than 2,200 in 1752. (DCB.)]
Des Herbiers, like so many of the new world governors which were sent from the old country, was unhappy at his post and asked repeatedly to be relieved of his duties. On August 3rd, 1751, Jean-Louis, Comte de Raymond arrived to take over from Des Herbiers as the Governor of Louisbourg. On September 13th, Des Herbiers sailed for France; and, within six months of his return, he died.