Near the end of the third decade of the sixteenth century, a five-volume set of madrigal and motet partbooks was assembled in Florence and sent as a gift—or "musical embassy"—to the English court of Henry VIII. The manuscript set—minus the missing altus part—has been owned since 1935 by the Newberry Library in Chicago; but until H. Colin Slim's exhaustive efforts, no thorough study of the history or contents of the partbooks had been undertaken.

At first encounter, these partbooks yield no clues concerning their provenance, their composers' names, or the reasons for their dispatch to England. In his search for this information, Professor Slim used the musicologists' customary tools, namely, biobibliography, concordances, and textual and musical analysis. But he also used bibliographers' tools not always employed by musicologists: watermarks, bindings, script, orthography, and illuminations.

As a result of his efforts, the author was able to identify nearly all the works' composers and the manuscripts' expert illuminator. He also presents a detailed description of the binding process and the probably background of the scribe, places the political and social references in the works, and determines the route the volumes may have taken after they left Henry's library.

By placing the date of the partbooks' arrival in England around 1528, Professor Slim suggests that the musical culture of the early Tudor court was less French than has hitherto been thought. Indeed, the presence of the partbooks in Henry's library makes them the earliest evidence of the Italian madrigal in England. The author also provides new and significant data on the artistic and historical position of Philippe Verdelot, the partbooks' most extensively represented composer.

Volume I of this set contains two parts. The first, dealing with the manuscript itself, contains the history of the partbooks, information on their origin, composers, texts, and their importance as a gift to Henry VIII. Part II, dealing with the music, discusses general musical traits, the motets, the madrigals, the results of collation, and the appearance of some of the Newberry motets and madrigals in other sources.