The library opened in 1926, designed by Bertram Goodhue — one of the most original American architects of the early twentieth century, whose other major works include the Nebraska State Capitol and St. Thomas Church in Manhattan. The Los Angeles building drew on Egyptian, Mediterranean, and Byzantine Revival influences in a combination that Goodhue called his "own style," decorating the building with hieroglyphs, torch-bearing figures, and a pyramid-topped tower that has made it instantly recognizable ever since.

The building sits on Fifth Street in downtown Los Angeles, a few blocks from Pershing Square, in a location that has remained in the heart of the city's civic center as everything around it has been rebuilt several times over. The exterior surfaces are covered with inscribed quotations and allegorical imagery that reflect the high-minded Victorian and Edwardian ideals about learning and civilization that informed public library construction at the turn of the century.

The first fire, on April 29, 1986, was the larger of the two. It burned for seven and a half hours. Firefighters from across Los Angeles responded, but the library's age, construction, and the sheer volume of flammable material made containment extremely difficult. When it was over, 400,000 volumes were gone — roughly 20 percent of the entire collection. Another 700,000 books sustained water or smoke damage.

A second arson fire followed on September 3, 1986, before restoration work had begun. That fire caused additional damage but was smaller in scale.

No one was ever convicted of setting the fires. An investigation focused on a man named Harry Peak, an aspiring actor who had been in the library the day of the first fire, but charges were never brought. The mystery of who burned the library has never been resolved.

The city's response began within days of the first fire. Volunteers formed human chains to carry surviving books from the damaged building. Freezing facilities were commandeered across the region — the books had to be frozen quickly to prevent the water that had been used to fight the fire from causing mold damage that would destroy what the flames had spared.

More than 40,000 volunteers participated over the following months. The campaign eventually raised approximately $5 million. The technical work of drying, cleaning, and restoring the surviving collection took years. A Shakespeare Fourth Folio was found during the recataloguing process — an item that had been in the collection without anyone knowing exactly what it was.

The city also used the fire as an occasion to plan an expansion that had been discussed for years. A new wing was added, doubling the library's capacity while preserving Goodhue's original building.

The restored library reopened on October 3, 1993, after seven years of closure. The restoration and expansion, designed by Hardy Holzman Pfeiffer Associates, was completed at a cost of approximately $213 million. The new Tom Bradley Wing, named for Los Angeles's longtime mayor, more than doubled the library's floor space.

The Richard J. Riordan Central Library — renamed in 2001 to honor the mayor who had been instrumental in securing the restoration funding — now holds more than 2.1 million items in its circulating collection. Its Department of Special Collections contains over 3 million historic photographs of Los Angeles, making it one of the primary visual archives of the city's history. The third-largest public library in the United States, measured by collection size, serves the largest city in a state with more public library branches than any other.