Keller also decorated theatres and furthermore created a monumental painting with the history of the Grand Duchy of Baden.
From the late 1870s, some of his painted works served as the basis for book illustrations, in particular for the books by the Egyptologist Georg Ebers who published luxury editions of stories about the lives and times of the ancient Egyptians. He played a major part in popularising Egyptian culture among the readers in late 19th century Germany.
Hargesheimer (28% buyer’s premium) in Düsseldorf offered a monogrammed, 2ft 11in x 2ft 4in (90 x 68cm) canvas by Keller in its sale on March 10.
Die Wächter des Tempels (The Guardians of the Temple), dated 1884, was painted en grisaille and was the basis for one such illustration in the luxury three-volume edition of the novel Uarda which was published in 1886. It depicts a scene from the book, in which a High Priest prevents the daughter of the Pharaoh Ramses II from entering the temple.
The guide for the painting was set at €5000, but the successful French buyer had to contend with fierce international competition: the hammer fell at €40,000 (£35,400).