Before I get to the question, I have to talk about the epic campaign that occurred around it.
So, I (playing as the British) and a French Ai ally started the game on the Verdon Gorge map against two German Ai. Game type and difficulty, Supremacy and Hard. Literally right off the bat, my French ally wanted to throw in the towel. I will admit that the first few minutes of the game were indeed questionable, as the Germans nearly overran both of our settlements with cavalry charges. Once I had gotten to the Capital age, things stated to improve. In order to attack our settlements, the Germans had to go through a narrow pass leading to some steep cliffs/hills they could climb up. I positioned two outposts and my fort above this position and was able to hold both combined German forces back for a while. Meanwhile the French, still wanted to surrender. There were still some groups of Germans who managed to get past the fortifications, but my brave redcoats and the resolve of a few grenadiers manage to keep them at bay for the most part.
*I will also have to admit that a certain resource cheat may have been used a few times in the following section.*
We began reaching the Industrial Age and things really began to become more epic and intense. The Germans began advancing more and more with companies consisting of Uhlans, Dragoons, Hussars, Jaeger & Grenadiers, and heavy artillery. Against such mounting odds, I had trained thirty Redcoats & Green Jackets, twenty Dragoons, and four Field Guns. Positioned just on the other side of the narrow pass that they would have to cross threw and with my artillery on the cliffs above, I shredded wave upon wave of Germans. A little later, I had to recruit some more reinforcements to hold the pass, so I sent in the Scots. Twenty Scots Guards and thirty Highlanders helped to hold the Germans off. And while all this was happening, the French were not being attacked, were building their economy, but hardly no soldiers. It was only after I had to quite the game that the French actually began to engage the Germans. At this point I had to recruit entirely new units of thirty Redcoats, thirty Green Jackets, twenty Hussars, and four Horse Artillery.
While looking at the stats, I saw that I had recruited only 248 and had managed to kill nearly 1,000 Germans just by myself. It was an amazing and fun game, which could have easily have lasted a few more hours had I not have to get ready for class.
Oh, I almost forgot the question! It was, does an Ai ally automatically want to surrender if they are facing more than one opponent?
"It is the mark of an educated mind to be able to entertain a thought without accepting it."