Complex sentence: It could be thought that the war ended here, however, Rokuemon's son, Senjū Tarō, rushed to Yashima no Hage-tanuki, who had trained before him.
Split into simpler sentences: It could be thought that the war ended here. However, Rokuemon's son, Senjū Tarō, rushed to Yashima no Hage-tanuki, who had trained before him.