De Lanessan was born in
Saint-André-de-Cubzac in the
Gironde department of
France and entered the
French Navy in 1862, serving on the
East African and
Cochin-China stations in the medical department until the
Franco-Prussian War, when he resigned and volunteered for the army medical service. He then completed his studies, taking his doctorate in 1872. Elected to the
Municipal Council of Paris in 1879, de Lanessan declared in favor of communal autonomy and joined with
Henri Rochefort in demanding the erection of a monument to the
Communards; but after his election to the
Chamber of Deputies for the
5th arrondissement of Paris in 1881 he gradually veered from the extreme Radical party to the
Republican Union, and identified himself with the cause of colonial expansion. A government mission to the French colonies in 1886-1887, in connection with the approaching
Paris exhibition, gave him the opportunity of studying colonial questions, on which, after his return, he published three works:
La Tunisie (Paris, 1887); ''L'Expansion coloniale de la France
(Paris, 1888), L'Indo-Chine francaise
(Paris, 1889). In 1891 he was made civil and military governor of French Indochina, where his administration, which led to open rupture with Admiral Fournier, was severely criticized. Nevertheless, he consolidated French influence in Annam and Cambodia, and secured a large accession of territory on the Mekong River from the kingdom of Siam. He was recalled in 1894, and published a justification of his administration (La Colonisation française en Indo-Chine'') in the following year. In the
Waldeck-Rousseau cabinet of 1899 to 1902 he was
Minister of Marine, and in 1901 he secured the passage of a naval programme intended to raise the French navy during the next six years to a level befitting the place of France among the great powers. At the general elections of 1906 and 1914 he was not re-elected, and retired from politics. He was political director of
Le Siècle, and president of the
French Colonization Society, and he wrote, besides the books already mentioned, various works on political and biological questions. He died at
Écouen, then in
Seine-et-Oise. ==References==