The exact origin and purpose of this manuscript is uncertain. It was begun in the 13th century, and added to in the 14th and 15th centuries. Most of its contents relate in some way to Ely Priory--many of them relating to a variety of private and public devotions--so it was presumably handed down from one Priory official to another. It appears to be a prayerbook, assembled for personal devotion. This page presents a calendar, an expected part of a prayerbook of this period. It would have served as a kind of personal organiser for the user, to tell them which saint's or other feast was being celebrated on that day. The third entry in blue, about half-way down this page, at 17 September, is an entry recording the dedication of the church of Ely. At the end of the line is a note that it is to be treated as a principal feast day. This is the sort of evidence that proves this book to have been prepared for someone closely connected with Ely.