The Gregorian calendar is currently the most common chronological system, named after Pope Gregory XII, who insisted on its introduction in the Catholic world. Many mistakenly believe that it was Gregory who came up with this system, however, this is far from the case. According to one version, the main inspirer of this idea was the Italian doctor Aloysius, who theoretically substantiated the need to change the chronology that existed before that.
The problem of chronology has been quite acute at all times, because the development of historical science in the country, and even the worldview of ordinary citizens, largely depends on what is taken as a starting point and what a day, month and year are equal to.
There have been and still are many chronological systems: some take as a basis the movement of the moon around the Earth, others consider the creation of the world as a starting point, others consider the departure of Muhammad from Mecca. In many civilizations, each change of ruler led to a change in the calendar. At the same time, one of the main difficulties is that neither the Earth day nor the Earth year lasts for a round number of hours and days, the whole question isvolume – what to do with the remaining balance?
One of the first most successful systems was the so-called Julian calendar, named after Gaius Julius Caesar, during whose reign it appeared. The main innovation was that one day was added to every fourth year. This year has become known as a leap year.
However, the introduction of a leap year only temporarily smoothed the problem. On the one hand, the discrepancy between the calendar year and the tropical year continued to accumulate, although not as fast as before, and on the other hand, Easter day fell on different days of the week, although, according to most Catholics, Easter should always fall on Sunday.
In 1582, after numerous calculations and based on clear astronomical calculations, the transition to the Gregorian calendar took place in Western Europe. This year, in many European countries, the fifteenth came immediately after October 4.
The Gregorian calendar largely repeats the main provisions of its predecessor: a regular year also consists of 365 days, and a leap year of 366, and the number of days only changes in February - 28 or 29. The main difference is that the Gregorian calendar excludes from leap years all years that are multiples of one hundred, with the exception of those that are divisible by 400. In addition, if according to the Julian calendar the New Year came on the first of September or the first of March, then in the new chronological system it was originallyannounced on December 1, and then shifted by another month.
In Russia, under the influence of the church, the new calendar was not recognized for a long time, believing that according to it the entire sequence of evangelical events was violated. The Gregorian calendar in Russia was introduced only at the beginning of 1918, after the Bolsheviks came to power, when the fourteenth came immediately after the first of February.
Despite much greater accuracy, the Gregorian system is still imperfect. However, if in the Julian calendar an extra day was formed in 128 years, then in the Gregorian this would require 3200.
