Frants Peter Diderik Henningsen was a Danish painter, illustrator and professor. His paintings depict unfortunate occurrences in the lives of middle-class people living in Copenhagen during difficult times. His connections with Denmark's more traditional, realist school encouraged criticism from many of his more reactionary contemporaries, especially Karl Madsen who objected to his appointment as a professor at the Academy in 1887. Erik Henningsen, also an artist, was his younger brother.