 In June 1787, the exercitiegenootschap of Gouda stopped princess Wilhelmina of Prussia, by the Vlist.A flying army unit under Adam Gerard Mappa occupied a number of cities in Holland, and another did the same in Friesland.They tried to take the vroedschappen into their own hands, shortly before Charles William Ferdinand, Duke of Brunswick the commander of the troops of king of Prussia occupied the Republic, on 13 September.