For what it's worth, it's definitely Japanese. The script is a mixture of Japanese cursive kanji characters (similar to Chinese characters) and Japanese hiragana phonetic characters. I can read some snatches of the writing (poem?), but cursive characters defeat me. The first column on the extreme right (the two characters) is probably the title of the work. The first three characters of the of the third column from the right reads "fune-no-ho," meaning "the sail of a boat." The writing is read from top to bottom, right to left. Sorry I can't be of more help!