Best known for conquering the aztecs and claiming mexico on behalf of spain
Well, you're in luck, because I can only think of two, haha.
The first reason would be because of the invasion of Barbarian tribe.
And the second reason would be because of the rise of the "Eastern Empire".
The largest population groups are:
5-9
10-14
15-19
20-24
These are the bars that are the furthest to the left, indicating the highest population.
Total population:
2 + 2.1 + 2.1 + 2 = 8.2