Here is the full list of all 18 Villagers achievements.
Few Villagers are better than none, though some more would also be fun.
You have completed Chapter 3
5 houses in your settlement
You have extended your Townhall
You have completed Chapter 2
You have completed Chapter 1
A baby has been delivered
Home, sweet home, your townhall is built. You better prove worthy or they will speak guilt.
Tü tütü tüüütütütü, dance!
More people are coming to town, now please don't let them down.
Your city is expanding! Take care, more people are demanding.
One hundred townsmen, this is a city! Having them starve would be a pity.
The raiders 've been stopped, the town is saved. You are the saviour, the path is paved.
You have completed Chapter 4
You have completed Chapter 5
You have completed Chapter 6
10 houses in your settlement
50 houses in your settlement