In August 1997, Tim Crawford read a paper at the International Musicological Society's Congress on some recently-discovered violin manuscripts from the former Breslau (now Wroclaw, Poland) Stadtbibliothek. Here is the abstract of the paper:
Scholars of the early violin in Germany have long been aware of the existence of a significant collection of instrumental music in the collection of the former Breslau (now Wroclaw, Poland) Stadtbibliothek. A catalogue of the music manuscripts was published by Emil Bohn in 1890, but the entire manuscript collection was thought to have been destroyed during World War II. Fortunately, however, the violin manuscripts are among the large number fom Breslau, Danzig (now Gdansk, Poland) and elsewhere that have been 're-discovered' since the reunification of Germany at the former East Berlin Deutsche Staatsbibliothek, Unter den Linden, Berlin, and they are now in the care of the Preussischer Kulturbesitz.
The collection as a whole is principally important for an enormous quantity of performance material for German church music of the early 17th century - especially that in polychoral style. Among the purely instrumental items, which include a famous set of canzonas by Adam Jarzebski (published in the 1960s from a prewar manuscript copy), two manuscripts in particular are of great importance in tracing the emergence of an idiomatic violin style in Germany, both in terms of the instrument's technique and its repertory.
Significantly, both MSS 114 and 115 also contain music for the viola bastarda, and a large proportion of their pages are taken up with embellishment examples copied verbatim from various Italian treatises (including: G. Bassano, 1585; R. Rognoni, 1592; F. Rognoni, 1620) in which the viola bastarda also figures prominently. The viola bastarda is also well represented as an ensemble instrument in the other Breslau MSS, suggesting that a school of players, probably trained by imported Italian masters, was at work in 17th-century Silesia and Poland. (The precise provenance of the collection has yet to be investigated in full.)
The interaction between the viola bastarda repertory and that of the violin is also attested by a manuscript in the Bodleian Library, Oxford, an English source which shares one virtuoso violin piece in common with Breslau MS 114. Further 'English' connections in the Breslau manuscripts can be traced through the repertory, which includes elaborately embellished versions of a few tunes of English origin (one or two of which may be masque dances) which also occur in other German sources, and at least one named composer, 'Stephan Naw' (Etienne Nau), who entered English royal service in 1629. This date may be taken as a plausible terminus ante quem for MS 114, which seems to have been copied by one 'Johannes Georgius Beck'.
Nau's Fantasia (MS 114, ff. 34-5), like many of the pieces in the collection, seems to be for unaccompanied violin. (The manuscript includes eight of the recercars for unaccompanied treble instrument from Bassano's 1585 treatise.) In some cases, however, it is hard to say whether the violin needs the accompaniment of a lacking continuo part, which is certainly true for some of the pieces (violin parts of a sonata by O.M. Grandi and some canzonas). An extensive repertory of variations over standard ground-bass patterns (passamezzi, bergamascas) is also included, whose accompaniment could have been improvised without written music, or even possibly omitted altogether.