Complex sentence: Portraits were his main work, but he also created historical scenes and small works known as "Kabinettstücke" as well as decorating the lustschloss at Wilhelmsbad; now a park near Hanau.
Split into simpler sentences: Portraits were his main work, but he also created historical scenes and small works known as "Kabinettstücke". He also decorated the lustschloss at Wilhelmsbad; now a park near Hanau.