The first public library in Centre County was the direct result of a bequest from Ann Elmira Humes, in her will of 1935. She left her house (the historic Miles-Humes home, built 1814-1815) at 203 N. Allegheny St. in Bellefonte to be used as a library, as long as the community would rally with financial support within a reasonable period of time.
The town, led by the Bellefonte Woman’s Club, did rally, and in 1938 the Commonwealth of Pennsylvania and Centre County agreed to help to provide funding. On October 25, 1939, the Library & Historical Corporation of Bellefonte opened in the big stone building at the northwest corner of Allegheny and Howard Streets, with a collection of 10,000 volumes. In 1956 the name was changed to Centre County Library & Historical Museum.
In 1977, the CCL renovated the former A&P supermarket building on the northeast corner of Allegheny and Howard Streets and transferred the main circulating collection of the Library to that site  on October 23, 1977.
The original Library building, the Miles-Humes home, houses the Pennsylvania Room  collections, four museum display rooms, and administrative offices.
The first county Bookmobile  took to the roads on December 24, 1941. The current Bookmobile is the sixth, and serves 29 different municipalities in the County, focusing on those areas which lack public transportation and nearby branch libraries.
The Philipsburg Public Library (later renamed Holt Memorial Library) became part of the Centre County Library system in 1963, followed by the Aaronsburg branch library in 1968. In 2010, the Aaronsburg collection was moved to Millheim to become the East Penns Valley Area Branch library. Unfortunately, in 2013, the branch was closed due to state funding cuts.