Johann Wilhelm, Duke of Jülich, Cleves and Berg (1562-1609) - Difficulties at the Düsseldorf Court

It is quite striking that none of De Castro's music volumes preserved from his Düsseldorf period were written for his new patron Johann Wilhelm; they were all dedicated to prominent people from Cologne.

However, historical sources about the life of Johann Wilhelm reveal a plausible reason for De Castro's apparent disloyalty. Shortly after De Castro's appointment as chapelmaster, the Duke began to suffer from increasing insanity. The standing and prestige of the Düsseldorf Court entirely declined, life at court fell prey to disrupting intrigues which would result - among others - in the tragic end of Johann's spouse: Jakoba of Baden was murdered on 3 September 1597.

Johann Wilhelm of Jülich, Cleves and Berg	Jakoba van Baden

Moreover, recent discoveries reveal that De Castro did show loyalty towards his ill patron. One of the letters De Castro wrote to Jan Moretus uncovers that he composed at least one music book for Johann Wilhelm, a book which now has been lost. (see letter of 20 November 1589).