Units all over the place and it took a little while to get my bearings. Read the last few posts, and saw that Fippy recommended we move north/northeast to Brennus' core. I agree. It looks much more important to deal with him than to kill off Stalin. Brennus got some units about, so I get some of the way back and rest on a hill. This is the main stack Brennus has in the area.
He throws some of that stack at us, and thankfully we win all defensive combats, though one cav withdrew.
The economy is in tailspin, and I take up the advice of gaining more overflow and then one-turning a bank. It doesn't help a whole lot, but a little (+26

). Don't recall what the plan was around the capital, but I converted another farm to workshop, and kept railroading. Not much else to do with the workers there, now when it's too unsafe to railroad in the open.
Oh crap. Bad news. Infantry
Our cannons won't have such an easy time now, relatively speaking. Genghis also gets into trouble, and actually loses a city. Denver falls to a Brennus counter attack. Brennus also poisons the well in Madrid. Really rude of him! Good thing we have traded for Biology, so it's easier to handle. Genghis could really use Infantry as well, so I sort that out for him.
Our main stack has arrived at Burgundian. Perhaps this was a mistake and I should have moved straight east, but my thinking was to clear some land and make it easier for Genghis to resettle the land, instead of Brennus and Stalin. Cannons only get 39% win chance, so we lose one or two here, but otherwise take the city without losses
I've gotten out some Artillery, mixed in with Infantry, because we'll need them now when Brennus has his own Infantry. Both attack Denver, but get 95% odds due to all those promos. CR3 artillery is no joke.
I don't want to take the city, though, as it will only get razed. Instead I leave one 3.0

infantry left, and hope Genghis will grab it himself. Plan succeeds.
Here is the main stack. They've healed for one turn, so most units are in good shape and ready to move. Think it's time to head into Brennus' core. Maybe produce more artillery, which can then add to the stack?
Not sure if the city count gets updated when at war, but it doesn't look like Stalin has resettled (much) land yet. Now when it's safer near the few cities Genghis has left, I hope he will found some more cities. He has at least one settler. The far western barb city hasn't been taken yet either, but then they probably have rifleman defenders by now. But shouldn't have infantry yet (they can get that, right?)