The rare-earth manganites RMnO3 (R = rare earth) are a class of important multiferroics with stable hexagonal structures for small R ion radius (Sc, Lu, Yb, ...). Metastable perovskite phases of these systems possess intriguing electronically driven electrical polarization, but the synthesis of the perovskite phase for the end member ScMnO3 system has proven to be elusive. We report the structure of a new monoclinic P2(1)/n perovskite phase of ScMnO3 synthesized from the hexagonal phase under high-pressure and high-temperature conditions. This extends the small ion region for so-called E-phase electronically driven ferroelectric manganese perovsites.