Libraries existed in America before the establishment of the ALA. The first public library in the U.S. is contested, but there are three generally accepted answers. The first is the Library Company of Philadelphia which was founded in November 1731 by Benjamin Franklin. It was a subscription library and supported by members.
The first free modern public library was opened in 1833. The Peterborough (N.H.) Town Libraries was the first institution funded by a municipality with the explicit purpose of establishing a free library open to all classes of the community.
The first library card catalog was created at Harvard in 1840.
That same year as Harvard developed the card catalog, 1840, the University of South Carolina opened the first separate academic library building. There had been university libraries before, but they were housed in multi-use buildings. The University of South Carolina Library is the oldest continually operated library building in the country.
Read more about the history of the University of South Carolina Library.
The first public library in the U.S. is contested, but there are three generally accepted answers. The last contender for this title is the Boston Public Library. It was the first free municipal library in a large community and was founded in 1848, almost thirty years before ALA
The first conference with the intent to form a permanent library organization was held in New York City in 1853. Unfortunately the follow-up conference, scheduled for the following year, was never held