Ise monogatari consists of 125 short stories, each including a poem or poems - a type of literature called uta-monogatari or 'poem-story'. The author is generally believed to be the poet Ki no Tsurayuki (868?-945?) and the protagonist, another poet, Ariwara no Narihira (825-880). It concerns many romantic escapades by Narihira and his aristocratic companions, and most of the stories begin with the well known sentence Mukashi otoko arikeri, 'Once upon a time there was a man'. The exact date of the work is unknown but is believed to be middle of the 10th Century