Janssen's significant murals include: • "" ("Colonization of the
Baltic Sea Provinces by the
Hansa. 1201."), in the
New Exchange in
Bremen (1872) • "" ("The Myth of
Prometheus"), 11 (possibly 12) part mural sequence, in what was formerly named the "second Cornelius Room" () of the
Alte Nationalgalerie in Berlin (18741876) • Six large and three smaller murals of scenes from the history of
Erfurt, in the (ballroom) of the (completed in 1882) • A group of frieze and ceiling paintings: "" ("Human Life"), "" ("Imagination"), "" ("Beauty"), and "" ("Nature"), in the (auditorium) of the Kunstakademie Düsseldorf (18861896) • Seven part mural sequence of scenes from the
legend of Otto der Schütz (Otto the Archer) and the history of
Marburg, in the (auditorium) of the
University of Marburg's (Old University) building (18951903) Some of Janssen's significant oil paintings: • "" ("The
Denial of Peter"), completed in 1869, was once owned by the
Pennsylvania Academy of the Fine Arts in
Philadelphia. • "" ("The Childhood of
Bacchus)", completed in 1882, was first exhibited in the , and is now displayed in the . The New International Encyclopedia described it as "a composition of great dramatic power, containing many life-size figures". In 1893 it earned Janssen a "great gold medal" at the first (Great Berlin Art Exhibition).
Selected paintings File:Hermann (Arminius) at the battle of the Teutoburg Forest in 9 CE by Peter Jannsen, 1873, with painting creases and damage removed.jpg|("The Victorious Advancing
Hermann")—
Krefeld, completed in 1873 File:FriedrichBarbarossa.jpg|Submission of
Henry the Lion to
Frederick Barbarossa— Erfurt, completed in 1882 File:Worringen 1288.jpg|("Walther Dodde and the Peasants of Berg at the Battle of Worringen")— displayed in Düsseldorf, completed in 1893 File:Peter Janssen, Kaiser Friedrich II.jpg|("
Emperor Friedrich II Dismisses
Teutonic Knights Moving to
Prussia 1236")— Marburg, 18951903 ==Sources==