Not much is known about Markus (or Marcus) Heinrich Grauel (or Graul). In his first lexicon Ernst Ludwig Gerber (1746–1819) dedicated a short article to the musician: “Graul (Markus Heinrich), Royal Prussian chamber musician and violoncellist in Berlin, born in Eisenach, held this position already in 1766. He is said to be a skilled and reliable ensemble player and composer for his instrument. A cello concerto of his composition is offered by music dealers in manuscript.” Apart from this there are only few other contemporary references to Grauel. When Charles Burney (1726–1814) during his travels through Europe visited Berlin in 1772, he found occasion to listen to Grauel in a concert: “M. Grauel, a violoncello performer in the King’s band, played a concerto; it was but ordinary music; however, it was well executed, though in the old manner, with the hand under the bow.”
In his Lebensbeschreibungen berühmter Musikgelehrten und Tonkünstler Johann Adam Hiller (1728–1804) mentions Grauel in his entry on the Strelitz concertmaster Johann Christian Hertel (1697/1699[?]–1754) as Hertel’s son-in-law. According to Hiller Grauel was a member of the court chapel of Mecklenburg-Strelitz until the ensemble was dissolved in 1753.
Before he was admitted to the Prussian court chapel on 1 December 1763, Grauel had already been employed as a cellist in the services of the Count of Schaffgotsch. As for the time between 1748 and 1756 a copyist by the name of Grau(e)l is documented at the Prussian court, it may be assumed that several persons of this name were active there.
As a musician employed in the Prussian court chapel Grauel apparently also had some teaching obligations. He died in 1799 in Berlin.
Hiller writes about Grauel: “Plays his instrument very well and composes beautiful concertos and solos for it.” Today only a small number of works can still be traced, and their attribution is uncertain. Whether the solo for viola and basso continuo mentioned in Breitkopf’s second supplement (1767) and headed “GRAVEL” was actually written by Grauel cannot be verified any more. Another problem arises from the fact that the similar names of the brothers Carl Heinrich (1703/04–1759) and Johann Gottlieb Graun (1702/03–1771), who as kapellmeister and concertmaster in the Prussian court chapel were active in the same environment as Grauel, probably facilitated misattributions. In any case, today are aware only of six compositions transmitted under the name of Grau(e)l: a sonata for violin and harpsichord in G Major (D-B, Mus. ms. 8140), a violin concerto in A Major (D-Bsa, SA 2684), a cello concerto in A Major (D-Bsa, SA 2686) and three viola concertos (in E-flat Major, D-Bsa, SA 2721/SA 2723; in C Major, D-Bsa, SA 2722/SA 3011; and in E-flat Major, D-Bsa, SA 2685 [a second copy of this concerto is transmitted under the name of “Graun”, D-Bsa, SA 2725; GraunWV Cv:XIII:116]). [...]
The work shares a number of stylistic features with solo concertos by Johann Gottlieb Graun, but there are also noticeable differences. It is striking, for example, that for the central movement Grauel chose the same key as he used for his outer movements and that it is written in multi-sectional lied form. Also, Graun’s concertos tend to be considerably longer. On the other hand the virtuosic demands on the soloist are at times rather violinistic.
Be that as it may, this is a well-crafted concerto of a quality that makes it a welcome addition to the viola repertoire of the 18th century.
Phillip Schmidt (excerpt by the preface)
 Ernst Ludwig Gerber, Historisch-Biographisches Lexicon der Tonkünstler, vol. 1, Leipzig 1790, col. 533
 Charles Burney, The Present State of Music in Germany, the Netherlands, and United Provinces, London 1775, p. 219.
 Cf. Johann Adam Hiller, Lebensbeschreibungen berühmter Musikgelehrten und Tonkünstler, neuerer Zeit, Leipzig 1784, pp. 162f.
 Cf. Christoph Henzel, Berliner Klassik. Studien zur Graun-Überlieferung im 18. Jahrhundert, Beeskow 2009, p. 152, footnote 68.
 See especially Friedrich Wilhelm Marpurg, Historisch-Kritische Beyträge zur Aufnahme der Musik, vol. III, Berlin 1757, p. 63. This probably refers to Johann Nepomuk Gotthard Graf von Schaffgotsch (1713–1775), a court official (“Preußischer Oberstallmeister und Minister im Generaldirektorium”); apparently he kept his own music ensemble in Berlin.
 Cf. Christoph Henzel, Berliner Klassik. Studien zur Graun-Überlieferung im 18. Jahrhundert, Beeskow 2009, pp. 151ff., also containing a facsimile of a letter by Grauel. See also Christoph Henzel, “Die Schatulle Friedrichs II. von Preußen und die Hofmusik (Teil 2)”, in: Günther Wagner (ed.), Jahrbuch des Staatlichen Instituts für Musikforschung. Preußischer Kulturbesitz, Stuttgart 2000, pp. 175–209, especially pp. 205f.
 See also the article “Rose, Johann Heinrich Victor”, in: MGG2, Personenteil, vol. 14, Kassel et al. 2005, col. 391f.
 Cf. Christoph Henzel, Die italienische Hofoper in Berlin um 1800, Stuttgart and Weimar 1994, p. 271. The Verzeichnis des musikalischen Nachlasses des verstorbenen Capellmeisters Carl Philipp Emanuel Bach, Hamburg 1790, p. 105, contains a reference to a drawing depicting Grau(e)l, which cannot be traced, however.
 Cf. Johann Adam Hiller, Wöchentliche Nachrichten und Anmerkungen die Musik betreffend, vol. 1, Leipzig 1766/67, p. 79 (2 September 1766).
 See Barry S. Brook (ed.), The Breitkopf Thematic Catalogue. The Six Parts and Sixteen Supplements 1762–1787, Reprint: New York 1966, Supplement II, 1767, col. 279.