@Pangaea - your army is way bigger than mine. I couldn't get peace as early as you did, because I lost a [poorly] settled city early on, and he got Iron connected, and the Praets are much tougher to beat up than the Axes.
He probably hooked up Iron earlier in your game, and got out Praets earlier because of that. He never actually invaded me with Praets, which as you say are much tougher to beat. They get easy winning odds against archers, even behind walls I suspect, so he'll build up war success. Axes only had 17% odds or something like that against my wall-protected archers, and all of them died. That meant it was possible to get peace with him once he had suicided enough units. You haven't been able to get peace yet?
Continued the game with the war. Took longer than I imagined, which I think was largely due to walls in every city except one, so I needed 2-3 turns to bomb away that first. Seemed futile to keep throwing catas against 8-strength units (or archers on hills) when they have 0.5% winning chances or something like that. All those archers kinda became a weight on the economy as well, and we paid 30+ gpt during the war for unit upkeep. I do think it helped to have 5 cities instead of 3 tho. It's not that easy to keep whipping out units, at least here with poor food, so it was useful with a few more cities. He actually surprised me by landing two units from a galley on top of the northern iron, so that needed some elephants diverted. Thought it was an exploring galley. City wasn't in dire risk because it had an archer as defence, plus a cata that hadn't left yet, and then got an elephant two turns later from the capital.
This is from 1 or 2 turns after the war ended, so I've whipped a few buildings and suchlike in the former Roman cities. Zara is by far the tech leader, with Longbows, so think it makes more sense to consolidate now, and have a go at him later. Settle that city in the south (to pick up fish and crabs), and grow the economy. We're already in Buro + OR, and will soon get Philo. The GG came too late to the front to promote units in a sensible fashion, so he's resting with the bulk of the army in Neapolis. It's swamped in Zara culture, so needs a pile of MPs.
The war could probably have been carried out better, as it did take quite a while, but take a look at the save if you want. Maybe there is something to be learned when coupled with the pre-war save. Depends how you do these things, and if I've messed up something along the way. If so, please point them out
(I'm not terribly pleased with my settling pattern in the north, as there simply isn't enough food to spread cities this thin, but at that point I was working on the assumption of a small 6-ish city empire, so they were settled with that in mind -- not warfare).
Upon loading the game to take these pictures, I see that we killed "only" 6 Praetorians. Quite lucky I'd say. But then I erroneously thought of them as Maces, so expected axes to be upgraded to Praetorians -- which of course is not possible (because they are Swords in disguise). The timely peace treaty must be why he had so few. Though he could have whipped more during the second war, I'm sure. But not after we took Rome, because then had no metal left.
A sizeable army left, though I think a new war needs better siege. Either trebs or wait until Cuirs or Cannons. Archers actually made quite a few kills as cleanup, but later on I had ample supply of elephants + axes, so they were just along for the ride (and to smash cottages for gold).