His approach defined the Norwegian decorative style during the late nineteenth century. Munthe often depicted domestic scenes and rural architecture, such as in his work Sval på Gaarden Sañar i Utterval. He simplified forms into geometric shapes and used a palette inspired by the natural dyes found in old peasant crafts. This method allowed him to bridge the gap between traditional folk aesthetics and the emerging Art Nouveau movement.

Modern collectors value Munthe for his ability to modernise heritage motifs. His prints offer a sense of calm through their structured compositions and clear, non-naturalistic tones. These prints suit contemporary interiors that favour clean lines and historical character. His work remains a primary example of how traditional Nordic themes can be translated into a sophisticated graphic language.