1798 Depot de la Marine Nautical Map or Chart of Coast of Vietnam

This is a scarce 1798 François Étienne de Rosily-Mesros nautical chart or maritime map of the coast of modern-day central Vietnam - marking the first inkling of French political interest in Vietnam. The map depicts the coast from modern-day Qui Nhon north to Chan May near Tourane (Da Nang). A large inset in the bottom left illustrates the coast north of Cape Choumay (Chan May) and includes an elevation profile view.

The First Inkling of French Interest in Indochina

When Rosily visited the coast of Vietnam in 1778 - 1779, the country was entering an extended period of political instability. The Tây Sơn Rebellion (1771 - 1802) led to the collapse of the Cochinchine Trịnh Lords and North Vietnamese Lê dynasty (1428 - 1789). The fifteen-year-old prince of Cochinchina, Nguyễn Phúc Ánh (1762 - 1820), was forced into exile at a local mission where he befriended the French Catholic priest Pigneau de Behaine (1741 - 1799). Behaine believed he could leverage Nguyễn Ánh's desperation for supplies and troops to gain both missionary and political status - for god and king, respectively. Behaine along with Nguyễn Ánh's son, Nguyễn Phúc Cảnh (1780 - 1801), traveled to Versailles where he argued Nguyễn Ánh's cause before Louis XVI. On November 21, 1787, the Treaty of Versailles was concluded between France and Cochinchina. Four frigates, 1650 fully equipped French marines, and 250 Indian sepoys were promised in return for full cession of Pulo Condore and free access to the port of Tourane (Da Nang) - central to this map. No sooner had Behaine left for Pondicherry (and thence Cochinchina), than Louis XVI, in increasingly dire financial straits, had second thoughts, sending an advance missive to the governor in Pondicherry, Thomas Conway (1735 - c. 1800), stating that he need not provide the promised ships, troops, or supplies. Conway did nonetheless dispatch Rosily and the Méduse to survey the coast in the vicinity of Tourane / Da Nang in 1778 - resulting in this map. Although official help was ultimately not forthcoming, Behaine pressed on, raising money to finance ships and troops from merchants in Macao. With Behaine's unwavering assistance, Nguyễn Ánh eventually defeated the Tây Sơn and in 1802 became the first Emperor of Vietnam, taking the name Gia Long. Although Louis XVI, himself about to be deposed, was less than sincere in his dealings with Behaine and Nguyễn Ánh, the Nguyễn dynasty retained a positive disposition towards the French, ultimately setting the stage for colonization in the 19th century.

Meanwhile, Back in France…

Back in France, the French Revolution (1789 - 1799) deposed Louis XVI. Rosily returned to France after the most violent stages of the Revolution, likely saving his life. He was appointed head of the Dépôt des cartes et plans de la Marine, a position he continued to hold under Napoleon until 1805. He took his maps and surveys of the Vietnamese coast with him, leveraging his influence to have the Dépôt engrave and publish them in 1798 - despite a loss of relevance.

Publication History and Census

The chart was based on the observations of Vice-Admiral François Étienne de Rosily-Mesros (1748, Brest - 1832), engraved by Jean-Baptiste Croisey, and issued by the Dépôt de Marine in 1798. Three examples are cataloged in OCLC and are part of the institutional collections at the Bibliothèque Nordique in Paris, the Observatoire de Paris, and the National Library of Australia.