don't see why he couldn't marry more than 1 as long as others are willing to be footwives/concubines although if he ends up marrying that viking princess then things might get complicated on marrying more than 1.
Yeah but Kaylan makes it very clear that she will not be just some concubine or side piece.
Aelinia makes it very clear that she will be the 1st wife and all others are beneath her.
Cassia will not tolerate to be under Valentina, well the both of them are like bickering children, about which is the better one....
The viking princess is not so much a problem, multiple wives, as well as concubins were very common in that culture (for the rich and powerful) to such a point that there was a shortage for the not so lucky males...solution was buying women and well capture them and then make them wives/concubines, they didn't go raiding just for gold...
In-game i don't find it very clear what is the norm in the Kingdom, one wife and concubines or multiple wifes ?
It doesn't help that all others don't seem to have multiple wives ...