Roku once told Aang something along the lines of “you have mastered the elements 1000 times and you will do it again” and people took this literally to mean that Aang was the 1001st avatar, or approximately so. But I always thought that had to be a gross exaggeration as a thousand-generation timeline would span back to before homo sapiens sapiens, and certainly before any sort of human civilization.
Soo I decided I wanted to figure out how many Avatars there have been realistically, and my primary source for this is going to be the Avatar Sanctuary in the Southern Air Temple, where Aang, Katara, and Sokka find statues of all the past Avatars, with Roku in the middle and spiraling outward with each previous Avatar, going up into darkness.
From this and the floor layout of the sanctuary, we can actually extrapolate and calculate how many Avatar statues there are in the sanctuary. I’m fairly certain that all the Avatars are featured here as well, because it looks to me that the spiral doesn’t continue on into darkness - the room isn’t filled to the ceiling. So somewhere way up there the first Avatar’s statue is gathering cobwebs, WHOM WE NOW EXCITINGLY KNOW TO BE SOME GUY NAMED WAN.
The article that revealed this also says that his story takes place 10,000 years before Korra’s - another rounded number, and certainly not 1000 avatars’ lives worth of years.
Anyway, with my calculations we’ll be able to figure out how many avatars there have been (definitely not 1000) and approximately how many years ago the first Avatar’s time was.
This is the ground level of the sanctuary.
It has 45 statues.
I overlaid an Archimedean spiral over the screenshot where the statues go up into darkness to figure out how many statues are obscured by the ledge/darkness and how many there are in one tier. Then I just added that amount for each tier.
Add this to the 45 on the ground and we have…
184 AVATARS IN THE ROOM(give or take about 10 I’m gonna say)
+Aang = 185
+Korra = 186
Now for calculating timespan I’m gonna ignore Kyoshi onward because of her really long life, and then the hundred year time gap in Aang’s life.
So up to and including Kuruk there are 182 Avatars.
Lets say the average life expectancy was 40 years during the reign of the first avatar, and was 80 during Kuruk’s reign.
We can use the equation for the sum of a sequence, Sn=n(a1+a2)/2, to find the sum of the first 182 Avatars’ lifespans, where n is the number of terms, a1 is the first and a2 is the last.
So: S=182(40+80)/2, and yields a total of…
+230 +70 +112 = 11332 years
Therefore, the first avatar was born about 11 thousand years before the events of Avatar: The Last Airbender.
If The Legend of Korra is based on approximately the year 1930 in our world, then Avatar was in 1860.
Therefore, the first Avatar lived in about the Avatar world’s equivalent of 10,140 BCE.
Earth’s neolithic revolution (which yielded the first permanent civilizations) was at the earliest circa 9000 BCE. Its not that much of a stretch that there were a few differences between our world and the world of Avatar, and their neolithic revolution was a bit earlier than ours. In this case, both bending, and the need for an Avatar to be the bridge between the spirit world and physical world would come with/as a result of the neolithic revolution. Makes sense.
But, the main result of this is that Aang was the 185th avatar and Korra is the 186th - based on my calculations, which I don’t think can be off by more than about 10 avatars.