Hokay! Grandbell's turn.
This is one fucking hugeass country with lots of independence within the Houses, so if I have anything wrong, someone please let me know!
So for individual houses:
Valhalla/Chalphy
Willfor has written a better and more comprehensive timeline
here. The summary: Chalphy takes over (causes political unrest), Arnold and Tyana bicker, eventually "make up", Arnold retires and Tyana is left as the regent. She will still be the regent when 2nd gen rolls in.
At Beth's request, the remaining Nargas will be quietly shoved aside, which will set off Kairos's angries, and he'll be back later wearing a mask and calling himself the scarlet pi-- oh wrong fandom.
Velthomer
With Finn's death and Althaea's disappearance, Velthomer continues to suck stays in the political rut it's been in. Finn did, however, spawn five children with different women before kicking it, and these children will be supported by different people within the flaky Velthomer government, which will in turn generate more political tension, and by 2nd gen things will be beautiful. Except not. In the meantime, the people pray and pray and pray and pray because that's all they have left to do.
Freege
Garion is stupid and impregnated Nikita Jungvy, so the two will marry, which will in turn jeopardize Miletos's relationship with both Freege and Jungvy, and possibly cause a lot of facepalming elsewhere. Maria will marry a commoner and cause other House Freege members (except for maybe the estranged ones like Alice) to facepalm. Garion will attempt to implement policies to free the laguz, which will cause more facepalming and public outcry. In other words, GG FREEGE.
Dozel
Going along with whatever suits their best interests, which likely results in supporting the Chalphy rule.
Edda
Although Ellius (who is really Elijah) is secretly of the not-happy crowd, Edda supports Chalphy anyway in fear of retaliation, which greatly disappoints some of the people, as Edda will have its very own set of underground political movements going on when 2nd gen starts. That aside, Ellius marries, pretends that his eldest child dies, so oh noes no one to use the Valkyrie. Excuse GET!
Jungvy
Between making more babies thanks to the rulers' amazing luck, they support Chalphy's rule as well! And get angry looks from Miletos's general direction.
Miletos
Not of the happy with Jungvy and Freege's union in marriage, cuts relations with both Houses - which does not include trading, mind, but don't expect Variel to ever see his sister again. That said, Orphe is a douchebag but a very keen ruler, and the Miletos region will for once be completely at peace with no amount of political unrest during the next 20 years.
The country in general:
House Chalphy makes for very good rulers, to be perfectly fair. However, while some people would marry the government were it a person, some people are not kosher with the way they took the throne (taking advantage of an old law of Chalphy's and basically stating late Queen Sarah is unfit to rule, taking her place instead, Willfor explained it better
here) or with the fact they don't have Narga blood.
The result is peace on the surface possibly in fear of getting Tyana's panties in a knot, political unrest underneath, possibly with minor insurgencies that would swiftly be dealt with and lots of little factions plotting underground.
That is the situation when second gen rolls in.
For the future, however:
Chris got pregnant, as we all know, and is having two children - twin boys. The eldest, Eron, is born with Joseph's major Loputous blood, and with minor Narga blood from his mother. The youngest, Aidan, is born with the mother's major Narga blood, and um Jesse does he have minor Loputous?
Anyway.
They'll have lived in the lower (and thus less freezing) area of Silesia until shortly before 2nd gen begins. Chris dies five years after giving birth, leaving Lysander and Ashlin to raise the children with Lysander naturally being the mother. Bla bla bla thing is they eventually end up in Grandbell.
One particular political faction with members in several cities will eventually stumble upon a certain pair of twins, and omg, Narga blood! They'll have found the avatars they need to rise in rebellion! Awesome! Fantastic!
The bottom line: poor unfortunate Eron comes in contact with the Loputous tome hidden in Valhalla. Cue possession by Loputous. Cue all hell breaking loose. Cue Tyana dying spectacularly.
Cue all noble houses being given the choice to side with him or die.
Cue puny rebel factions rising! ...Cue lots of puny rebel factions getting crushed. Cue smarter puny rebel factions that don't get crushed! Cue plot! Cue traveling around the world and finding allies in unlikely locations! Cue shit, I forgot my lockpick! Cue fuck, stupid fucking weak thief died, restart chapter! Cue stat-less level-ups! Cue the evil RNG! ...Okay I'm done now.
Yeah, Grandbell, your future is down in the gutter, have fun with it.
And that's about it! Did I forget/misinterpret anything? Does anyone have any questions, concerns, NO Us, etc.?