The Louisiana State Museum’s (LSM) origins date back to the late 1890s, when the Louisiana Historical Society (LHS) established a repository for historic documents and artifacts. In 1900 the Louisiana legislature established a provisional state museum and two years later a state commission to create an exhibition for the 1904 Louisiana Purchase Exposition in St. Louis. That exhibition was reconstituted for LSM, which presented it at Washington Artillery Hall in New Orleans in May 1905. The following year, the legislature made the museum permanent. 

In 1908 the city of New Orleans transferred the Cabildo and the Presbytere to the museum, and on April 30, 1912, the museum held its grand opening to celebrate Louisiana’s statehood centennial. In 1926 philanthropist and preservationist William Ratcliffe Irby left the Lower Pontalba Building, the Jackson House, and the Creole House to LSM. The Works Progress Administration undertook several projects at LSM in the mid-1930s, including major renovations at the Presbytere and the Lower Pontalba. WPA workers translated and indexed the colonial documents and conserved painting. In 1947 Stella Hirsch Lemann donated Madame John’s Legacy to the museum; the building opened to the public two years later, one year after the museum added the 1850 House museum in the Lower Pontalba to its roster. 

The Friends of the Cabildo (FOC) organized in 1956. Since that time, the FOC has provided financial support, volunteer efforts, and many other contributions to the museum. In 1981, the Louisiana Museum Foundation, a nonprofit organization, was founded to accept and administer grants and community donations on behalf of LSM.

The federal government transferred ownership of the Old U.S. Mint to the Louisiana State Museum in 1966. After extensive renovations, the building opened to the public in 1981, in part housing the Louisiana Historical Center, which gives researchers access to LSM’s document and map holdings. In 1977 the New Orleans Jazz Club donated one of LSM’s most-renowned collections, the Jazz Collection, which includes Louis Armstrong’s first cornet.

On May 11, 1988, a fire inflicted heavy damage on the Cabildo, destroying the third floor. The historic treasure was restored and reopened in 1994. LSM expanded three times in the following decade, acquiring the Wedell-Williams Aviation Museum in Patterson in 1995, the Old Courthouse Museum in Natchitoches in 1998, and the E. D. White House in Thibodaux 2001. A new Patterson facility was completed in 2005, with a redesigned aviation exhibition opening in 2008; the building also houses the Cypress Sawmill Museum. The Capitol Park Museum opened in Baton Rouge in 2006. In 2013 the Louisiana Sports Hall of Fame and Northwest Louisiana History Museum opened in Natchitoches. The Old U.S. Mint became home to the New Orleans Jazz Museum, a branch of the state museum based on its renowned jazz collection, in 2018.