MONROE, a city of Louisiana, U.S.A., the capital of Ouachita parish, in the northern part of the state, on the east bank of the Ouachita river, 72 m. W. of Vicksburg, Mississippi, and 96 m. E. of Shreveport, Louisiana. Pop. (1890), 3256; (1900), 5428 (2834 negroes); (1910), 10,209. It is served by the Arkansas, Louisiana & Gulf, the Little Rock & Monroe, the Vicksburg, Shreveport & Pacific (Queen & Crescent), and the St Louis, Iron Mountain & Southern railways, and by river steamers plying between New Orleans and Camden, Arkansas. Across the Ouachita is the town of West Monroe (pop. in 1910, 1127). The improvement of the river, by the removal of snags and the construction of dams and locks in order to give it a navigable depth of 10 ft. at Monroe and 6½ ft. beyond Camden, was nearly completed by the United States government in 1909. Monroe lies in a level valley, and has broad streets shaded by live oaks. Among the public buildings are a handsome city-hall, a city market-house, a charity hospital and a high school. There are also a parish high school and St Hyacinth's Academy (Roman Catholic). The leading industries are the manufacture of lumber and cotton products.
In 1785, during the Spanish occupation of Louisiana, Juan Filhiol, commandant of the district of Ouachita, founded a settlement on the site of the present Monroe, which was called Ouachita Post until 1790 and then Fort Miró, in honour of the governor-general. In 1819 the place was renamed Monroe, in honour of President James Monroe, and in the following year the town was incorporated. Monroe was chartered as a city in 1871, and received a new charter in 1902.