From The Encyclopedia of Arkansas History and Culture:
The Carnegie Library at Morrilton, known as the Conway County Library, received a grant of $10,000 on September 29, 1915, with construction taking place at 101 West Church Street and completed in October 1916. The Pathfinder Club, a women’s organization established in 1897, was the driving force behind securing the grant to establish a library. Purchasing a lot downtown for its location, they used books from the library they had started among themselves. The 3,628-square-foot building cost around $7,500, with the remainder for furnishings. Here again the architectural style consists of a stairway leading to a dominant front door between large pillars. Morrilton achieved the distinction of being the smallest town in America to have a Carnegie library at the time of its opening, and the library gained National Register of Historic Places status on April 15, 1978. A new addition was completed in 2000, but the original Carnegie building is still in use as of 2011. 
From the River Valley & Ozark newspaper in 2015:
The Pathfinder Club applied to the Carnegie Foundation for a grant to build a new library and, in September 1915, Morrilton received $10,000, a “matching grant,” Green said, that had requirements that didn’t include cash. The requirements included Pathfinder members as staff, the land that already was purchased and a guarantee of perpetual financial support for the library from the city.
The Conway County Library opened in October 1916. 
From the Only in Arkansas website:
MORRILTON. We can thank the determined ladies of The Pathfinder Club for the Carnegie library at Morrilton, known as the Conway County Library. What started as more of a social club for sharing personal books (first Arkansas book club perhaps?) became the group that solicited funds from residents to purchase real estate for future library construction. Armed with a prime downtown lot and an impressive, rare book collection donated by Morrilton resident W. S. Cazort (later known as the Porter Collection), the ladies qualified for a $10,000 Carnegie grant. Funds were used to construct the library, buy furniture and coal for heating.
Current Status: The original building, added to the National Register of Historic Places in 1978, is still in use as a free public library.
Interesting History: At the time of its opening in 1916, Morrilton achieved the distinction of being the smallest town in America to have a Carnegie library. 
From a personal telephone conversation with a Conway County Library librarian on October 5, 1916:
Joshua: "I have not been able to narrow the date further than October, 1916 in my research. Does the library maintain a record as to the precise opening day?"
Librarian: "That would be October 4th, 1916. Now, that's the date out of this building. The library was operating before that."
Joshua: "That would be the Carnegie building, correct?"