Poetry trait?

[Princeps]

How get I the poetry trait or start to write poets? All my Vassals send me poems, but i cannot do it in the dplomacy tab.

[Maffeketel]

You get it through a random event or you'll have to choose it when creating your ruler.
I got it randomly when I was a jarl. It's a pretty useful trait to have and it also gives you piety as it is considered a virtuous trait.

It mostly depends on luck and there are no specific things that you can do to make it trigger. It is a diplomatic trait and my character was focused on warfare so it is definetly completely random based on my observations.