Howdy, welcome back to Discovery! We're always happy to see returning face -- especially roleplayers -- so to help you (somewhat) acquaint yourself with the current climate of the Discovery sector (more specifically, the political side, as you've asked), here's a summary:
Liberty: Currently wrapping up an insurgency on Planet Erie, Pennsylvania; investigating an active alien ruin in Ontario; beginning preparations for an invasion of Inverness alongside Crater
Bretonia: Assembling forces for the Liberation of Dublin with Kusari assistance; working with the Great Houses (vanilla ones, to be exact) in restoring the supply of Gold Ore
Rheinland: Rebuilding still after a bloody civil war; preparing to make moves in the Omegas and Sigmas for more resources; ramping up support for the Gallic Union as per the signing of the Treaty of Oerlikon and subsequent deals on exchanges of food stocks and raw materials
Kusari: Recovering from catastrophic flooding on Planet Kyushu; assisting Bretonia in their up-and-coming Dublin campaign with jump drives (they have already tested the canonical jump drive prototypes in a region of Kusari space -- find out on your own where!)
Gallia: Rebuilding; currently throwing a kickass party after Rheinland has signed a crucial deal over the above listed materials (note on Gallia: they did some Atrocities -- to understate things -- and are now a pariah state with little to no support outside of their Great House and Rheinland proper)
This, of course, only explains the Colonies. The Border Worlds have undergone much change too, frankly too much to summarize in one post. If you've questions on lore, feel free to reach out to me here, over Discord, or right here in this thread. I'll happily answer any lore questions you have, at least the ones I am certain I have an answer to!
