Consists of medieval and renaissance documents and manuscripts collected by Richardson. Of principal interest are some 350 documents (deeds, bonds, contracts, investitures, wills, and other legal documents), chiefly dating from 1380 to 1550 and written in Milan, Alessandria, Brescia, Cremona, Lodi, and other northern Italian cities. Included are a series of documents pertaining to the monastery of San Pietro di Civate (near Como) and to other religious houses. Each notarial document come with a 19th-century description in Italian.

There are also approximately 150 other documents. Including a selection of papal bulls, and documents from Rome, the Austro-Hungarian Empire, England, Ireland, and the United States, chiefly dating from the 17th-19th centuries. The collection also contains a numbered series of 25 bound manuscripts (chiefly canon law treatises and collections of documents pertaining to the history of the Roman Catholic church), copied by Italian scribes in the 17th-18th centuries.