Let's say as the Romans, I am at war with Germany, conquering a lot of German cities and installing new governors in each one. That reduces the German cultural influence. Meanwhile, however, this allows the influence of a third party (say, Egypt), who is not involved in the war on either side, to come flooding in. Indeed, depending on the situation, Egypt may wind up gaining more territory from the war than Rome does. In such situations, I have tried building "culture generators" like libraries and such in the newly conquered cities, but that doesn't much help the problem of them flipping to Egypt. I even tried sending settlers and putting them in Egypt's path, but that didn't really help either. So what am I supposed to do in this situation? Am I supposed to crank up my culture slider a lot higher?