Schiller's contact with the Meiningen court librarian Reinwald resulted in a very fruitful intellectual friendship between the two men. Reinwald was nearly 50, a bitter, disappointed, yet highly educated man, somewhat of a Stubengelehrter (a closet literary man) who had taken on the daunting task of translating into High German from Old Saxon the medieval story of 'Heliand'. He had also written a glossary to this translation, but could not find a publisher. Ultimately, Reinwald donated the work to the Bavarian State Library in Munich. A letter Schiller's sister Christophine had written to her brother on behalf of her father accidently was left behind in Meiningen. Reinwald read it and became fascinated by Christophine. He subsequently courted and married her in 1786.
While Schiller's play 'Fiesco', which premiered in Bonn that year, deals with the subject of the conspiracy against the house of Doria in Genoa in medieval times, the play 'Luise Millerin', which the Mannheim actor Iffland would later coin 'Kabale un Liebe', is again set in Schiller's own time. It describes the uncessessful love affair of Ferdinand, son of President von Walter, who has control of the affairs of a small German state, with Luise Miller, the daughter of a musician. After all direct efforts to break up their affair fail, Ferdinand's father resorts to intrigue and coerces Luise to write a letter implicating herself in an illicit affair with a court official. This is accomplished by von Walter's threats to the life of her father. Ferdinand, on receiving this letter, prepares a poisonous potion to kill them both. This tragic outcome cannot be prevented, as Luise feels bound to her 'oath' given to von Walter, from explaining herself to Ferdinand. Ultimately, von Walter and his secretary are brought to justice for earlier misdeeds that now come to light. This drama is described as a Buergerliches Trauerspiel (bourgeois tragedy).
Schiller's contract as Mannheim theater poet stipulated that he was to write three plays in one year, of which two were already written: 'Fiesco' and 'Luise Millerin'. Due to his malaria infection, however, Schiller would soon run into difficulties in trying to fulfill this contract. His recuperation was delayed due to his own radical self-treatment, and the effect of the illness would linger with him until well into 1784. Researchers also discuss the possibility as to whether this infection was not the starting point of his later illnesses.