Trained as an engraver by his father, Rahl studied at the academy from 1827. He traveled to Germany, England and France, and spent two years in Rome, where he made friends with Josef Anton Koch, one of the leading German artists in the city. He became professor at the academy in 1850, but was dismissed in 1851 because of his participation in the 1848 revolution. While removed from the academy, he ran a popular private school in which Romako and other artists worked and collaborated with the master on sveral large fresco projects. Rahl was reappointed to the academy in 1863 after Kupelwieser's death. He became Vienna's leading proponent of Monumentalmalerei, or monumental painting, and was the central figure in the city's artistic life at mid-century. He was largely responsible for the reintroduction of color in monumental frscoes after a long period influenced by the dry graphic style of such Nazarenes as Josef Führich. Rahl's huge allegorical and historical scenes for the staircase of the Armory and in the public buildings designed by Theophil Hansen represent the pinnacle of his artistic career. Rahl was also a popular portrait painterm again bringing a greater interest in color to his portrayls.

Erika Esau, Pre-Modern Art of Vienna 1848-1898, Edith C. Blum Instutute of Bard College, 1987.