Yes, Cagil and Tara won on Atamara because of two major things.
1) The two realms were united at the hip. If you fought one, you fought the other. Except for a very small handful of times. Cagil declared peace with Carelia while Tara was fighting them and left Tara to try to sue for peace. That was a bad time for Tara for a while. But the vast majority of the time, the two realms acted near enough as one that it was almost impossible to break them.
2) Cagil was VERY good at buying off or otherwise convincing other realms to side with Cagil and Tara even against other friends. No alliance was safe from Cagilan money or other forms of diplomacy. Just about every war we won, we did so because Cagil pealed one or two nations off the other side and got them to come over to our side. Of course, none of those nations still lived in the end. Every single one was targeted and destroyed in later wars. Only Tara and Talerium were never victim of such a strategy.
And yes. In the end there was no alliance of nations that could hold against the Cagilan-Taran Alliance. All nations that survived to the end did so because they became allied with Cagil, Strombran, or Tara and used the Federated Status of those big three to keep from being targeted.
That situation became untenable when Strombran and Cagil chose to destroy Carelia which was allied with Tara. Multiple Taran Tyrants resigned in a row over that situation. And when I became Tyrant I was informed in no uncertain terms that I had to give up Carelia. I couldn't say no because Tara was too disorganized to stand up to either Cagil or Strombran at the time. But I did welcome all the Carelian nobles into Tara and used them to help revitalize my nation and make it strong again. The Carelian general became my general for instance. And I spent the next year working to get the other members of the League of the Eagle to realize that the situation as it was could not continue.
I was of course smart enough to never SAY that. Not when it would have turned into a Taran clubbering at the hands of the other nations. But I and my general had this understanding. He did things I of course would never condone. And when it came out that he did that...well...then he had to be ordered back...but...you know...the army marched, broke some stuff, and then came home. Refitted. Went out and hunted some monsters. Came back. Refitted. Went out and smashed something somewhere else. I would of course apologize and call them back. Dang general getting a bit frisky and all that. Not that I ever told him to go do it. Honestly. I didn't. Though I may have made some idle wishes known.
So he played the belligerent and got our armies moving and doing things and marching as a real coherent force while I worked to restrain my overzealous general for the League of the Eagle.
Then Strombran bellied up to the table and went further than I was ever prepared to go when it came to stuff like that. Heck. They played belligerent, admitted in total in the League of the Eagle, and basically dared anybody to call them on it.
Like I said. I spent a year trying to get everybody to see that the current power structure was unworkable. That it stifled the continent. And I was not the only one who was doing that. I wont give out names, but I was in contact with a LOT of people who were working very hard to break up the League of the Eagle. People both within the League and without. And in the end, we convinced the entire League of the Eagle that we were right. It had to be broken up.
Once the League came to an agreement on that point, we talked about doing it in an orderly manner that would have kept us on top and in charge of the surviving power structure. We actually came up with several very interesting plans to do that. I generally argued for plans that would significantly weaken all four of our realms. Each one would have broken up into two or three realms, each with no more than two cities to give us parity with the other realms on the island. My proposals were the most radical. We had a lot of very interesting plans on "how to fix things whilst remaining in charge" as Shulee so elegantly put it.
In the end though, we did not initiate any of those plans. We couldn't really agree on any of them. All we could agree on was that the situation had to change. So...we just rolled the dice. Granted, I'd spent the last year LOADING my dice, but when I pulled Tara out of the Federation and started the war, it was one heck of a roll of the dice. And there was every chance that Tara would be utterly destroyed doing it. There was no guarantee at all of remaining in charge.
The "elite cabal" at the heart of the League of the Eagle just agreed to shake everything up, bring down the power structure as it was, and see where things led. There was every possibility that we were sealing our doom in a war that would destroy all of our realms. We each wanted to make certain it was the OTHER realms that fell of course, but we were all willing to accept the risk that it would be ours instead. Or all of ours.
None of us knew where it was going to lead, and I'm very sorry that we never got to find out what was going to happen.
I generally focus my projections on two direction. Best case and worst case.
Best case. Talerium, Minas Leon, Tara, and the southern alliance work together to smash Cagil and Strombran, forcing some of their dukes to break away or die, and leaving them a shattered group of city states. It's MY best case. Sue me.
Then Tara breaks up into two or three nations that are each no more powerful than any of the other nations on the continent, and...bang...power structure reset with me in charge of Foda and that's about it...that would have been my happy "ending" for the war.
My worst case ending was Tara getting into a knock down drag out fight with Cagil and Strombran, only to be jumped by Minas Leon and the southern alliance when they decided that they could still have a chance of taking out Cagil and Strombran without Tara on their side. Now I was doing everything I could diplomatically to make sure worst case did not happen to Tara, but our little Tyrant and General Two Step had pissed off most of the realms on Atamara to a lesser or greater degrees. So...yeah...I consider the worst case scenario to have been VERY possible. Maybe even probable.
But that was the risk we all took when we decided to destroy the existing power structure on Atamara.
