well you also have to consider the games playability vs historical accuracy
a string of bad luck basically means you go game over only because you dont have a son inheriting that can keep your dynasty alive
Yes, that's probably the sole biggest reason 'matrilineal marriage' is in the game. The downside, though, is that it overemphasises the 'surname' and also leads to things like Salian/Capet/Piast/Jimena/whatever baronesses extending the dynastic name through multiple female links.
Also, matrimarried daughters will inherit before brothers, uncles and such like, of whom you may have quite a pool.
Finally, the sheer frequency of use by the AI is troubling.
btw ... historically most of the marriaged we are talking about (female ruler marrying someone "lower status") led to their children becoming a cadet branch
i.e. the Queen of House Herpaderp marries some Noble of House Huehuegurp ... their children most likely became "of House Herpaderp-Huehuegurp"
but since this game doesnt support Cadetbranches in its current state CK2 cant reproduce that without the player going game over.
Yeah, that's similar to the Hasburg-Lorraine example I cited above.
The typical reality was that lands and titles were inherited by in-laws, and in some cases the titles would be kept separate, e.g. the kids would generally assume dad's surname but one of them would take mum's and continue the titles. This happens even modernly, in order to avoid e.g. an ancient barony or Scottlish clan chieftainship becoming another subsidiary title held by a duke. So basically a younger son gets mum's titles and surname instead of everything sticking to the eldest like under normal rules. You could even call that a version of gavelkind.
On the other hand, modern views focus very legalistically on inheritance from the previous holder as opposed to some sort of dynastic ownership of titles*. This has resulted in Queen Elisabeth II matrimarrying, even though there were (and still are) patrilineal Windsors in existence who were not her descendants – for example the Dukes of Gloucester and the Dukes of Kent are descended from her father's younger brothers, which is very close IMHO. Her children were made to continue the Windsor dynasty to avoid a dynasty change, but in any case they would have inherited the throne even as Glücksburgs and princes of Greece and Denmark.
Curious fact: Prince Phillip was born as a prince (and of both Greece and Denmark, actually). They
made him give it up so he could marry Princess Elisabeth without holding foreign titles (he went untitled for half a year) – despite being a foreign prince. Talk about someone going nuts about nationalism etc.
* Dynastic ownership of titles vs succession strictly from the previous holder is also what makes a good deal of countries and societies different from France and England (yes, even much of Germany/old HRE had this sort of dynastic community thing).
... In any case, I'm glad that the AI doesn't use matrimarriage as the habitual way of simply having a larger dynasty the way human players do. On the other hand, I'd rather that royal surnames wouldn't be pased on by baronesses to her children born of a lowborn father. Baronesses belonging to houses like Salian, Capet etc. would basically be like the counts of Vermandois, whose name on release was NOT Karling. They were simply 'de Vermandois'. Just like even the Lancasters and Yorks didn't walk around using 'Plantagenet' as their name. Most nobles were named after their holdings, which could result in a large number of different 'surnames' within one family. Dynastic names like Salians, Capets, Piasts etc. are the invention of historians, NOT the kind of surnames like even those known to republican Roman families (the Flavii, Cornelii, Claudii and such like). This with the exception of Byzzies, Armenians and such like.
Also, since gameplay's been mentioned. Suppose a Capet is married off to a countess somewhere in Spain. Possibly better than being untitled, though I guess hanging out at the French court and being of the same dynasty as the liege would've been even better (at least you didn't have a duke for a liege and only then some small-time king like Gallicia, while you're of royal French stock). Generations later the duchy ends up being held by the king or destroyed. The count, a 'Capet', with possibly 2-3 matrimarriages in his genealogical tree, can drag a slew of French dukes and even the king of France himself into his rebellion, with the right CB (some CB's don't allow you to call allies to arms). Having royal roots is cool and dandy, and it's certainly remembered in family tales, but being able to drag the Kaiser or the king of France into your wars for 'same dynasty' is an exaggeration. They could extend the comital house like that, but spawning a whole new generations of royal Capets? Nope.
Then again, I guess you have to simplify things to make them convertible into a computer game mechanic. Still, in late historical starts Naples and Hungary are ruled by the d'Anjou dynasty (a third house of the name, not to be confused with the Plantagenets, who were cadets of a previous line of d'Anjous). They can call each other to war, but they can't call France. The same is true for the Latin emperors – even though the first Courtenay emperor was a great-grandson of
Louis VI of France in legitimate male line. However, curiously, one could claim that the marriage of
Peter of France to Elisabeth de Courtenay (the parents of the emperor
Peter II de Courtenay, who succeeded Baldwin of Flanders, the first emperor) was a matrimarriage, since he became 'Peter of Courtenay' basically.
Well, anyway, you were typically known as 'Dude of Dudesbackyard' regardless of your parentage. 'Dudesbackyard' was typically synonymous with 'Dadsbackyard', but if dad owned no backyard, then it could be 'Mumsbackyard'. So basically if it goes like this:
Lord Tankard I of Bogeyville
Lord Tankard II of Bogeyville
Lord Tankard III of Bogeyville
... etc. etc., and at some point Lord Tankard IX has only a daughter, then perhaps there will be for a time a Lord Whatshisname of Bogeyville, followed by Tankard X of Bogeyville and so on, pretty much because Bogeyville is the only thing to name themselves after, anyway, as they only own Bogeyville, and Tankardings (after Tankard I) makes no sense because they're all named Tankard anyway (sort of like
these guys, but I think I've seen numerals go up to XL or something in one other German house). The Lords of Bogeyville care that they are Lords of Bogeyville, but they probably don't care much about the surname/dynasty business (they think like: 'we've lords here since times immemorial/our valiant founder centuries ago,' and that's it). Heck, 'Capet' as a surname was invented for the 'trial' of Louis XVI. Kings to this day insist that they have no surnames in the strict sense. In the past, this was true way further down the feudal ladder.
