Calendar of saints

The calendar is a traditional Christian method of organizing a liturgical year on the level of days by associating each day with one or more saints, and referring to the day as that saint's feast day. The system arose from the very early Christian custom of annual commemoration of martyrs on the dates of their deaths (Dies Mortis, day of death, opposite of Dies Natalis). As the number of recognized saints increased during Late Antiquity and roughly the first half of the Middle Ages, eventually every day of the year had at least one saint who was commemorated on that date. Eventually, some saints were moved to another day in some traditions, or completely removed; thus, some saints do have more than one day.
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