The close group of fine masonry buildings which were ranged to the south of the City of London's Guildhall in c. 1500 exemplified the often seamless way in which civil power, Christian religion, cultural life and economic activity were fused together in the late medieval world. It also represented the high point of a process of growth, expansion, and enrichment in this area of the City which bad lasted for more than 200 years. One of these buildings was a 'public' library, built by the executors of Mayor Whittington's will in c. 1424, and coming under the jurisdiction of the chantry college attached to nearby Guildhall chapel. The building was in use for over 125 years before it was seized as part of the closure of the chantries and colleges under Edward VI. This brief summary looks at the known history of the building, for which it is indebted to the work of Caroline Barron.(1) Archaeological remains, many of them substantial, were found of parts of the yard itself, the chapel, and of the college/library during recent excavations.