Most of the roughly 150 pieces of art chosen for the exhibit, ranging from marble antiquities to Baroque weaponry and European paintings, were sold during a liquidity crisis in the late 1930s, then reassembled for the show, according to LACMA.
The "Hearst the Collector" exhibit, which also includes objets d'art on loan from Hearst Castle, will run through Feb. 1.
The collection includes arms and armor, silver, Renaissance tapestries, Limoges enamels, and medieval treasuries of Renaissance goldsmiths' work.
The paintings include works by such artists as Boucher, Copley, David, van Dyck, Fragonard, Gerome, Greuze, Lawrence, Lotto, Reynolds and Vouet, and the sculptures are by Canova, Clodion, Marin, Sansovino and Thorvaldsen.
Hearst was known for his classical antiquities, which came from historic British collections, but his passion for California and the American frontier, exemplified by his collection of 300 Native American textiles, set him apart from traditional American collectors in New York and Boston, according to the exhibit curators.
On loan from Hearst Castle is the marble Lansdowne Venus by Antonio Canova.
Four full suits of armor come from the Metropolitan Museum of Art and the Detroit Institute of Arts.
A jewel-like sword, a pair of inlaid Baroque guns and a nearly 30-inch-tall gold cup that can hold almost three quarts of wine will also be on display, along with drawings by Hearst Castle architect Julia Morgan, the first woman to earn a degree from the Ecole des Beaux-Arts in Paris.