Additionally it is thought to house the largest collection of secular stained glass in the world.

After the death of the Browning's only son Robert Barrett Browning and subsequent sale of their collection, Dr. Armstrong obtained a list of the items sold and their purchasers, and attempted to acquire the memorabilia via donation or purchase.

The Carroll Library was heavily damaged in a 1922 fire; none of the Browning works were lost, and a special room was subsequently built to house them.

Construction on the library (which would also house the English department) began in 1948 and the finished structure (costing US$1.75 million) was dedicated in 1951.

The building was significantly renovated in 1995 to house an even larger collection (by then the English department had relocated) and refurbished in 2012.