Reading the Past
Measuring historical time
Read and write dates as BCE and CE, count the years across the gap where no year zero sits, and say which century or millennium a year falls in.
History is the study of the human past. To place what happened, a historian needs a way of saying when — and each society and culture has had its own. A major event, such as the birth of an important person or the start of a ruler's reign, has often marked the beginning of a new era, and the counting started again from there.
Counting the years
The calendar commonly used worldwide today is the Gregorian calendar. In the West its starting point has generally been taken to be the conventional year of Jesus Christ's birth. Years counted forward from that point used to be marked AD; they are now called the Common Era, written CE. Years counted backward from it used to be marked BC; they are now called Before Common Era, written BCE.
Have a play
One line, running from the distant past on the left to the future on the right.
Tap any part of the picture.
The missing year
That gap matters when you count across it. Since 1 CE follows straight after 1 BCE, adding a BCE date to a CE date counts one year that is not there. So the rule is: add the two numbers, then subtract 1.
Worked example
About 560 BCE is given as the year of the Buddha's birth. Taking the present year as 2024 CE, how many years ago was that?
Add the two numbers: 560 + 2024 = 2584.
One of them counts backward from the starting point and the other forward, so together they span the whole gap between the two dates.
Try it together
Now work out which century a year belongs to.
A century is any period of 100 years. In history, centuries CE are counted in blocks of 100 years starting from 1 CE — so the 1st century CE runs from 1 to 100, and the 21st century CE runs from 2001 to 2100.
1.Suppose a king was born in 320 CE. The 1st century CE covers years 1 to 100, the 2nd covers 101 to 200, the 3rd covers 201 to 300. Which year does the 4th century CE end on? Answer with a number.
Have a go
Your turn: which century CE does the year 1776 belong to? Answer with a number.
Hint: Find the block of a hundred years it sits in, then count how many blocks of a hundred that is since 1 CE.
Ready to practise?
Eight questions on what you have just read. Nothing is timed, and you can play as many times as you like.