Original: Johann married Maria Magdalena Keverich in 1767; she was the daughter of Johann Heinrich Keverich, who had been the head chef at the court of the Archbishopric of Trier.
Simplified: Magdalena's father, Johann Heinrich Keverich, had been Chef at the court of the Archbishopric of Trier at Festung Ehrenbreitstein fortress opposite to Koblenz.