In the middle ages, cathedrals and monasteries kept chronicles or lists of important events relating to the Church and the community. Chronicles could play a role in enforcing the community's claims to property and other rights, and also they recorded the post-biblical history of Christianity, showing the community's place within it. This chronicle belonged to the wealthy and powerful cathedral of Ely. The chronicle begins with early events in Britain. Near the top of the page, the martyrdom of St Alban (in the year 304) is recorded. Farther down, at year 603, the mission of St Augustine, initiated by Gregory the Great to convert the Anglo-Saxons, appears, followed further along by the founding of the monastery of Ely by St Athelthreda in 673.