While Itami was focusing all her efforts on her campaign in Borneo, Berengar was rather lax about the whole situation. He spent very little time in his war room, catching up on the latest updates. The reason behind this was simple.
Over the past fifteen years, he had established a highly competent chain of command that was entirely capable of waging war without his input. And since this was a proxy war at the moment, there really wasn't much that Berengar needed to do himself.
This was something that Empress Itami Riyo was completely lacking in her own government, and as a result, she was forced to micromanage every second of the war that she was awake for. As for Berengar himself, he had a very important meeting with another German Monarch.
