Help Creating Background For Campaign

What I have: I have a custom campaign world set up, with a bunch of lovely maps, some basic starting factions, a general history, and basically everything to actually start the campaign. What I need help with: I am trying to come up with a system that manages the background stuff of the different factions. As a month passes, which factions grow? which ones shrink? which declare hostilities or make peace? assassination attempts? diplomacy? trade influence? This is not a campaign focused on political intrigue. I try to run a fairly open ended campaign where I do a little bit of prep, try to throw in a little randomization here and there, see where the players want to take it, then do my best to improvise in response to the randomness and the players' choices. Therefore, the purpose of this thread is to design, or copy, a system that throws a little randomization into the background politics which may or may not have anything at all to do with whatever the players are pursuing.

The best way such a thing could be achieved on Roll20 (to my mind) is either via the API ( a mentor level perk ) or by using extensive rollable tables and a bit of elbow grease. With the API it would be possible to write a script that would look for certain events (you typing !month-end or something) and apply a random set of events in motion such as the assassinations, diplomacy etc which it could whisper to the GM or make amendments to faction character sheets (ie. a sheet for the Blue Star Trading Coster would have attributes set up that reflected its relationship with various factions, the script would modify these and whisper any serious issues to the GM such as if it fell below 0 with a rival trading firm there could be a 'war' or if the city it operates out of outlawed them it would reduce the relationship to -5 or something?). Using character sheets and rollable tables you can achieve much the same thing but manually. Set up a bunch of tables for the different levels of intrigue and roll on them at the end of each month to update the character sheets for the factions. (ie. one table would be for good relations and could incorporate several positive outcomes and a handful of negative ones to produce a declining relationship. Another table could be negative but with a handful of positives... you get the picture, the main thing is setting weighting appropriately). That way a few rolls on the tables will allow you to update the faction sheets and you can work anything major into the campaign as gossip, side quests or main quests. Or you could use a spreadsheet... or a pen and paper... or draw things from a hat :)