A somewhat mysterious medal, unlisted as a medal in the recent Corpus Numismatum Omnium Romanorum Pontificum (Volume III) published by Adolfo Modesti in 2004. References for this design, however, do go back to two of the earliest books on papal medals: Numismata Pontificum Romanorum quæ a tempore Martini V usque ad annum M.DC.XCIX by Filippo Bonanni (published in 1699) and Numismata Romanorum Pontificum præstantiora a Martino V ad Benedictum XIV by Ridolfino Venuti (published in 1744). Modesti does make note of the engraving of the reverse design which is present in Bonanni, but regards it as an emblem of Gregory XIII which was erroneously published by Bonanni as a medal.

Uno Boncompagni was born on January 7, 1502, was elected to the papacy on May 13, 1572, took the name of Gregory XIII, and died on April 10, 1585. This medal is dated to his thirteenth and final year as pontiff. Venuti neglects mention of the regnal year in the transcription of the obverse inscription, and Bonanni's work records only reverses. Both works do identify the medal as a memorial to the pontiff, which would indicate a posthumous issue.

The reverse inscription is adapted from Psalm 18:7 (Vulgate): A summo caelo egressio ejus. Et occursus ejus usque ad summum ejus; nec est qui se abscondat a calore ejus. (His going out is from the end of heaven, And his circuit even to the end thereof: and there is no one that can hide himself from his heat.) The design would seem to extoll the accomplishments of Gregory, with his achievements reaching all the Earth, just as do the rays of the sun. The small dragon featured on both the obverse and reverse is a device taken from the Boncompagni coat of arms.