And although the concept of “century” is introduced in history lessons at school, often not only children, but also adults get confused when it is necessary to correctly determine the beginning and end of this time period.
Bit of theory
Under the term "century" in history, it is customary to call a period of time of 100 years. To understand how to determine from which year the 21st century began, like any other, you need to know one small nuance of the generally accepted chronology. Everyone knows that the time of origin of all events is chronologically divided into two periods: BC and after. That's just what date stands at the turn of these two eras, not everyone knows.
Have you ever heard of year 0? It is unlikely because 1 year BC. e. ended on December 31, and the next day a new year came, 1 year n. e. That is, 0 years in the generally accepted chronology simply did not exist. Thus, a one-century-long period of time begins on January 1 , 1 year, and ends, respectively, on December 31, 100 years. And only the next day, January 1, in 101, a new century begins.
Due to the fact that many do not know this seemingly insignificant historical feature, for quite a long time there was confusion about when and in which year the 21st century will come. Even some television and radio presenters called for the celebration of the new year 2000 in a special way. After all, this is the beginning of a new century and a new millennium!
When the 21st Century Began
Calculating from which year the 21st century began, given all of the above, is not at all difficult.
So, the first day of the 2nd century was January 1, 101, 3 - January 1, 201, 4 - January 1, 301 and so on. Everything is simple. Accordingly, answering in which year the 21st century began, it should be said - in 2001.
When the 21st century will end
Understanding how the chronology of time is conducted, one can easily say not only from which year the 21st century began, but also when it will end.
The end of the century is determined similarly to the beginning: the last day of the 1st century was December 31, 100, December 2–31, 200, December 3–31, 300, and so on. Finding the answer to this question is not so difficult. The last day of the 21st century will be December 31, 2100.
If you want to calculate from which year the new millennium is counting, you should be guided by the same rule. This will avoid errors. So, the third millennium according to the Gregorian calendar, adopted by an absolute majority of world states, began on January 1, 2001, at the same time as the beginning of the 21st century.
Where did the general error go?
In Russia, the chronology adopted today was introduced by decree of Peter I. And before that, the count was from the creation of the world. And after the adoption of the Christian chronology, instead of 7209, the year 1700 came. People of the past were also afraid of round dates. Together with the new reckoning, a decree was issued on a merry and solemn meeting of the new year and the new century.
In addition, one should not forget that with the adoption of Christian time calculus in Russia , the calendar remained Julian. Because of this, for all historical events before the transition to the Gregorian calendar (1918), two dates are determined: the old and the new style. And because of the different lengths of the year adopted in each of the two types of calendars, a difference of several days appeared. And so in 1918, with the introduction of the Gregorian calendar after January 31, February 14 came.