Antique Japanese Meiji Era Signed Scroll Hand Written Calligraphy

This is a Meiji era (c.1900) antique Japanese scroll with a hand written calligraphy. There are a signature and signature stamps on the left side, Iwamitsu (see picture 5). The calligraphy is about praising the emperor. 
This scroll is approximately 73" long by 17" wide (185.5 x 43 cm). The actual artwork is 48" high by 12" wide (122 x 30 cm). Having been rolled up and stored for over 100 years, it remains in good condition.