|Location||North Riverside Mall, Baton Rouge, Louisiana|
|Architect||Gadsden,Capt. James; Hill,John|
|NRHP Reference #||73000863|
|Added to NRHP||July 26, 1973|
The Pentagon Barracks is a complex of buildings located at State Capitol Drive at River Road in Baton Rouge, Louisiana, in the grounds of the state capitol. The site has been used by the Spanish, French, British, Confederate States Army, and United States Army and was part of the short-lived Republic of West Florida. During its use as a military post the site has been visited by such notable figures as Lafayette, Robert E. Lee, George Custer, Jefferson Davis and Abraham Lincoln.
French, British and Spanish Fort
In 1779, during the American Revolutionary War, the British erected a dirt Fort Richmond on the banks of the Mississippi River. Bernardo de Gálvez, Spanish Governor of Louisiana, arrived at Baton Rouge on 20 September 1779 and found three hundred British troops garrisoning Fort Richmond. In the Battle of Baton Rouge (1779), engineers under Spanish Governor Gálvez quickly constructed a siege line, enabling the Spanish troops to shell Fort Richmond; the British surrendered the next day. The Spanish garrisoned the fortification and renamed it Fort San Carlos.
Republic of West Florida
American and remaining British settlers in Louisiana resisted Spanish control and rebelled in 1810 to establish Republic of West Florida. They raised the "Bonnie Blue Flag" of Republic of West Florida over Fort San Carlos throughout the short 90-day life of the Republic. The Republic turned over the city of Baton Rouge to United States of America on 10 December 1810.
United States Military Post at Baton Rouge
American forces renamed the fort Post at Baton Rouge. The Post at Baton Rouge served as the assembly point for American troops going to the Creek War in 1813-1814 and to the Battle of New Orleans in 1814-1815. The Army built the Baton Rouge Barracks just north of the Post at Baton Rouge and demolished it in 1819.
United States Army Captain James Gadsden designed the Baton Rouge Barracks and took charge of their construction from 1819 to 1825. The soldiers completed four two-story brick buildings, forming four sides of a regular pentagon, by 1825, hence the nickname "Pentagon Barracks." They also built a commissary-warehouse building, forming the fifth side of the pentagon, in 1821, but tore down this defective building within a few months due to poor construction. The Pentagon Barracks could house one thousand troops.
The Army in 1825 established a large adjacent Baton Rouge Arsenal and Ordnance Depot to serve the then-southwestern United States.
American Civil War
The United States Army occupied the Baton Rouge Barracks and Arsenal until January 1861, when the State of Louisiana seized the post and turned the operation of the arsenal over to the Confederate States of America. The Confederacy held Baton Rouge until its evacuation during the Battle of New Orleans in April 1862. Union troops retook and reoccupied the Baton Rouge complex in May 1862.
The Confederates attempted unsuccessfully to retake Baton Rouge Battle of Baton Rouge (1862) (in August 1862). Union forces renamed the Pentagon Barracks and Baton Rouge Arsenal as Fort Williams after Union General Thomas Williams, killed in the battle. Union soldiers built earthworks to protect the complex, incorporating an old Indian mound into the defenses.
Louisiana State University
In 1884, the General Assembly of Louisiana passed a resolution allocating the full usage of the buildings and grounds of the Pentagon Barracks to Louisiana State University. The University gained full possession of the grounds in 1886 and remained there until moving to the current location of the campus in 1926.
In 1951, ownership of the Barracks was transferred to the State of Louisiana and in 1976, it was placed on the National Historic Register..
The Pentagon Barracks now houses the offices of the lieutenant governor, the Pentagon Barracks Museum and Visitors Center, and private apartments for state legislators.