The seals were used to authenticate documents, according to Don Skemer, curator of manuscripts in the Department of Rare Books and Special Collections. The most important items are royal charters on parchment that were issued under the Great Seal of the Realm, which in Willsie’s collection date back to the reign of King John (1199–1216). Two-sided pendant seals usually were attached to their documents by a braided silk cord or a parchment tag.
The documents illustrate the “day-to-day business” of English government, Skemer said, such as confirmations of land tenure, rights and privileges, and judicial decisions. While official “record copies” were retained centrally in locations like the Tower of London, the documents in the Willsie collection were personal copies to be kept by the recipients.