I have almost no defenses on that starting area, so unless I move some forces there immediately, the island is pretty much gone. I had two large armies to defend myself on the mainland, but all of a sudden, Hojo's bitch tits come out of nowhere and drop a massive invasion force on my starting island at Awa.
All of my trade was gone, and my treasury went completely red. When the realm divide hit, I was pretty much instantly fucked. I established some really lucrative trade with several major clans, and conquered almost all of the mainland section directly north of the Chosokabe start island. I finally managed to make it into the 1560's as the Chosokabe for Short Campaign.