Myron Hunt designed the Library in 1919 as a purpose-built research facility for Henry E. Huntington's rapidly expanding collection of rare books and manuscripts. The building sits in deliberate relationship with Hunt and Elmer Grey's earlier residence across the lawn, forming a ceremonial pair at the heart of the estate. Completed the same year the Huntingtons established their nonprofit educational trust, the 96,000-square-foot structure embodied an unprecedented act of cultural philanthropy: a private collector building a public research library, endowing it, and giving it away while still alive to see it function. The five original trustees included George S. Patton Sr., whose son would become the Second World War general, and astronomer George Ellery Hale, who was simultaneously transforming Throop Polytechnic into Caltech and establishing Mount Wilson Observatory.
The building employs a restrained classical idiom that defers to the residence while asserting its own institutional dignity. Hunt worked with Harold Coulson Chambers, who had joined the office as a draftsman in 1907 and would become partner the following year, and McNeal Swasey on the design, with landscape architect William Hertrich integrating the structure into the estate's botanical collections. The Library Exhibition Hall displays the collection's treasures to the public, fulfilling the Huntingtons' explicit intention to benefit the public at large. Five subsequent additions have expanded capacity while maintaining the original building's classical restraint, the largest being the 2004 Munger Research Center.
