The never-published work of Boym, which covers an extensive manuscript of almost 70 pages, entitled "Brevis Sinarum Imperii Descriptio", to this day remains in the darkness of the Archivum Romanum Societatis Iesu (Jap.-Sin. 77, 33-66). This is a collection of information on 17th-century Chinese history - mainly relating to the dramatic circumstances of the overthrow of the Ming Dynasty and the seizure of power by the Manchu Qing Dynasty.
The author enriched the history with various types of additional, ethnographic and geographical information, and above all, a broad description of the activities of the Jesuits in China and their activities at the court of Emperor Yongli, crowned with numerous conversions in the imperial family and the mission to the Pope, which Empress Helena entrusted him with.
Boym`s text competed with Martino Martini`s text "De bello Tartarico Historia" published in 1655 while Michael Boym sat confined in Loreto, Italy.