When does the Third Millennium begin?

As we approach the end of the Second Millennium, there appears to be mass confusion as to when the new millennium begins.  Of course, when the first millennium ended, and the second began, there was a rash of religious mania that confused the issue, just as we have our modern-day millennium nuts. That is no excuse, however, for confusing a simple matter of how many years are in a decade, a century, or a millennium. Therefore, below is a simple chart that will help clear up the matter for those who are otherwise confused. If you are looking for something more authoritative, try the US Naval Observatory or the Royal Observatory Greenwich. If you are having difficulty understanding the concept in English, try it in Italian or German. In addition, I have found a few other sites of related interest you might want to visit. And, finally, I give you a link to an interesting dissertation on the number zero which, although it's conclusion is wrong (since there is no year 0), it helps to explain much of the history of the number zero, our system of reckoning dates, and ultimately, of this controversy.

This table ignores conversions to and from the Julian calendar, which are immaterial to this discussion

Description of date

Number of years A.D.

Date, A.D.

The first day, the first year, Anno Domini
(Also the first decade, century, & millennium)

Less than 1 (ca. .003)

1 January 1
The end of the first year, A.D.

1

31 December 1
The end of the first decade, A.D.

10

31 December 10
The beginning of the second decade, A.D.

10.003

1 January 11
The end of the second decade, A.D.

20

31 December 20
The end of the first century, A.D.

100

31 December 100
The beginning of the second century

100.003

1 January 101
The end of the second century

200

31 December 200
The end of the first millennium

1000

31 December 1000
The beginning of the second millennium

1000.003

1 January 1001
(Query: Do you begin to see a pattern emerge?)
The beginning of the 18th century

1700.003

1 January 1701
The beginning of the 19th century

1800.003

1 January 1801
The beginning of the 20th century

1900.003

1 January 1901
The end of the 20th century (or 2nd millennium)

2000

31 December 2000
The beginning of the 21st century (or 3rd millennium)

2000

1 January 2001

Does this help clear up the confusion? If not, here is another table that puts it more simply, and with less need to detect simple patterns.

First year 1 January 1 to 31 December 1
First decade 1 January 1 to 31 December 10
First century 1 January 1 to 31 December 100
First millennium 1 January 1 to 31 December 1000
1001st year 1 January 1001 to 31 December 1001
101st decade 1 January 1001 to 31 December 1010
11th century 1 January 1001 to 31 December 1100
First 11 centuries 1 January 1 to 31 December 1100
First 20 centuries 1 January 1 to 31 December 2000
Last day of the 2000th year 31 December 2000
Last day of the 200th decade 31 December 2000
Last day of the 20th century 31 December 2000
Last day of the 2nd millennium 31 December 2000

First day of the 3rd millennium

1 January 2001, a.k.a. 1-1-2001

Any questions or comments? If so, please write me at jtr@jtridenour.com. I welcome any intelligent comments!

Links to other sites of interest

2001 - A New Millennium This site contains a countdown to the new millennium, other information, as well as a comprehensive list of other links.
Datalus 24/7 - The Millennium "2001" Countdown A countdown to the new millennium.
Das neue Jahrtausend beginnt 2001 A German site.
The New Millennium Starts 2001 The previous site in English.
L'INIZIO DEL TERZO MILLENNIO An Italian site.
Millennium 321 "An intelligent, interactive & entertaining portal to the best of the web."
Is the Millennium 2000 or 2001? An ABC News report
Number of seconds till Millennium-2001 Find out how many seconds until the 21st Century.
Millennium An explanation of how to count dates.
The new Millennium in 2001 An Australian site.
The TRUTH about decades, centuries, and millennia! Another extensive list on links.

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