India Company (1734). These jobs kept him in and around the Hague. After his brother died in 1745 he moved into the Van Wassenaer house in the Kneuterdijk. A year later he was admitted into the Dutch knighthood. Unico Wilhelm continued to spend part of his time at Twickel, and in 1726 he had maps made of this property and the rest of his inheritance. In 1744 Unico Wilhelm was sent on a diplomatic mission to the French court, and in the autumn of 1744 and again in 1745 he was sent to the court of Clemens August, Elector of Cologne. In 1746 he went again to France, and finally in 1746–47 to Breda for further discussions with the French. Although clearly intelligent, Unico Wilhelm was not a natural diplomat. Unico Wilhelm was a commander of the Bailiwick of Utrecht of the Teutonic Order. He was made coadjutor in 1753, and introduced administrative and managerial innovations. In 1761 he was made Commander of the order. He died in The Hague on November 9, 1766. Music While based at the Hague between 1725 and 1740, Unico Wilhelm wrote the six Concerti Armonici. The Concerti armonici, published anonymously in 1740, were printed in London in 1755 as compositions by the violinist and impresario Carlo Ricciotti (c. 1681–1756). It has since been established that these were the work of Unico Wilhelm. There is no evidence that Ricciotti wrote any music. The concerti were dedicated to Wilhelm's friend, Count Willem Bentinck. The slow movements of the concerti have expressive beauty. The Polish composer Franciszek Lessel (1780–1838) asserted incorrectly that the concertos were written by Pergolesi. Since the style of the concertos is Italian, laid out in typical Roman fashion with four parts for violin and consisting of four parts instead of the Venetian three, they are comparable to works by Pietro Locatelli. However, in 1979–1980 a manuscript of the six concerti was found in the archives of Twickel Castle (the castle where Van Wassenaer was born) labeled "Concerti Armonici." Although the handwriting was not by Van Wassenaer, the manuscript did have an introduction in his hand, reading: "Partition de mes concerts gravez par le Sr. Ricciotti". Because of the research done by the Dutch musicologist Albert Dunning, there can be no doubt that the concerti were, in fact, written by Van Wassenaer. Dunning quotes the composer's Foreword in full-- "Score of my concertos, engraved