Plan of Louisbourg in 1779
Detailed plan of the town and port of Louisbourg, oriented with west at the top, made by order of the French Depot de la Marine, during the American Revolution.
The plan was originally made 2 years prior to the Siege of Louisbourg in 1758, with this example re-issued in 1779 as part of a set of maps and charts issued to the French Military at the outset of France's formal involvement in the American Revolution.
The map show the fortifications and buildings in and around the harbor, along with roads, Batterys and the Royal Magazine. A meticulous depiction of the soundings in the harbor is shown along with topgraphical details.
The map was created as an aid to French Mariners in 1779. France formally recognized the United States on February 6, 1778, with the signing of the Treaty of Amity and Commerce, which was immediately followed by signing the Treaty of Alliance in anticipation of conflict as a result. Hostilities soon followed after Britain declared war on France on March 17, 1778.
The Dépôt de la Marine, known more formally as the Dépôt des cartes et plans de la Marine, was the central charting institution of France. The centralization of hydrography in France began in earnest when Jean-Baptiste Colbert became First Minister of France in 1661. Under his watch, the first Royal School of Hydrography began operating, as did the first survey of France’s coasts (1670-1689). In 1680, Colbert consolidated various collections of charts and memoirs into a single assemblage, forming the core of sources for what would become the Dépôt.
The Dépôt itself began as the central deposit of charts for the French Navy. In 1720, the Navy consolidated its collection with those government materials covering the colonies, creating a single large repository of navigation. By 1737, the Dépôt was creating its own original charts and, from 1750, they participated in scientific expeditions to determine the accurate calculation of longitude.
In 1773, the Dépôt received a monopoly over the composition, production, and distribution of navigational materials, solidifying their place as the main producer of geographic knowledge in France. Dépôt-approved charts were distributed to official warehouses in port cities and sold by authorized merchants. The charts were of the highest quality, as many of France’s premier mapmakers worked at the Dépôt in the eighteenth century, including Philippe Bauche, Jacques-Nicolas Bellin, Rigobert Bonne, Jean Nicolas Buache, and Charles-François Beautemps-Beaupré.
The Dépôt continued to operate until 1886, when it became the Naval Hydrographic Service. In 1971, it changed names again, this time to the Naval and Oceanographic Service (SHOM). Although its name has changed, its purpose is largely the same, to provide high quality cartographic and scientific information to the France’s Navy and merchant marine.