The Comprehensive Genealogical Feast Day Calendar compiled by Inger M. Bukke, Peer K. Kristensen and Finn A. Thomsen  

 

Most saints and holy people have specially designated feast days. On those days we remember these holy men and women in a special way.

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.

This calendar system, when combined with major church festivals and movable and immovable feasts, constructs a very human and personalised yet often localized way of organizing the year and identifying dates. It may be compared with the roman Missal.

Many children acquire baptismal or confirmation names from the saint associated with his/her date of birth, baptism or confirmation, and believing Eastern Orthodox Christians (and in some countries, Roman Catholics) mark the "name day" (namesday) of the saint whose name he/she bears with special attention, often instead of birthday celebrations.

The Julian calendar was a reform of the Roman calendar which was introduced by Julius Caesar in 46 BC and came into force in 45 BC. It has a regular year of 365 days divided into 12 months, and a leap year day is added to February every four years. Hence the Julian year is on average 365.25 days long.

The Julian calendar remained in use into the 20th century in some countries as a national calendar, but it has generally been replaced by the modern Gregorian calendar. It is still used by the Berber people of North Africa and by many national Orthodox churches. Orthodox Churches no longer using the Julian calendar typically use the Revised Julian calendar rather than the Gregorian calendar.

 

The Gregorian calendar is the most widely used calendar in the world today. A modification of the Julian calendar, it was first proposed by the Calabrian doctor Aloysius Lilius, and was decreed by Pope Gregory XIII, for whom it was named, on 24 February, 1582. Years in the calendar continue the numbering of the Julian calendar, which are numbered from the traditional birth year of Jesus, which has been labeled the AD era, and is sometimes labeled the "common era" or the "Christian Era".

The changes made by the Gregorian calendar was to correct the drift in the civil calendar because the mean Julian calendar year was slightly too long, causing the vernal equinox, and consequently the date on which Easter was being celebrated, to slowly drift forward in relation to the civil calendar.

The Gregorian calendar system dealt with these problems by dropping 10 days to bring the calendar back into synchronization with the seasons, and adopting the following leap year rule:

Every year that is exactly divisible by four is a leap year, except for years that are exactly divisible by 100; the centurial years that are exactly divisible by 400 are still leap years. For example, the year 1900 is not a leap year; the year 2000 is a leap year.

 

This Comprehensive Feast Day calendar is divided into six sections:

            1.  The index to fixed and movable feast days.

                        The index consists of an alphabetical listing of fixed and movable feast days. If the feast day is fixed, meaning that the date is

                        the same every year, the day and month is given in the column "Date of Number". If the date is moveable, meaning that the

                        feast day can vary up to 35 days, depending upon the year, a number is listed in the column "Date of Number". This number refer

                        to the first column (No.) in the  third or fourth section (depending upon the calendar in use in the area for that time period).

            2.  Dates of changes from Julian to Gregorian calendars.

                        This section is used to determine when a country changed from the Julian to the Gregorian calendar.

            3.  The movable Feast Days tables - Julian calendar.

                        The third section of the calendar consists of movable feast day with the day and the month of each feast day recorded in the column

                         of the year. The day and the month of the desired movable feast day is recorded by the number obtained in the index, in the column

                         of the year.  Use this section for MOVABLE Feast Days for the Julian calendar.

            4.  The movable Feast Days tables - Gregorian calendar.    

                        The fourth section is arranged the same as the third section; however, this section MUST be used for the Gregorian calendar.

            5.  The movable Feast Days tables for Sweden and Finland.

                        This section of the calendar is arranged the same as sections three and four. It is to be used for Sweden and Finland for the time

                        period 1700-1712.

            6.  The French Republican calendar.  

                        This section is to be used for the countries using the French Republican calendar for the time period 1792-1805.