The Samurai's Tale, by Erik Christian Haugaard, is a fiction novel published by Houghton Mifflin Company in 1984.
[1] He loses his parents when he is young and is then captured by Takeda Shingen, eventually becoming a servant of one of his generals, Lord Akiyama.
Eventually, Shingen dies, and his son - Takeda Katsuyori - takes over his father's realm.
Meanwhile, Taro has become a samurai, received a new name, and fought with a man named Lord Akiyama, who proves to be an able commander by taking over Iwamura castle from to Toyama's.
[1] Katsuyori proves to be incompetent, ignores advice from the retainers of his father, and shuns lord Akiyama, whose castle is eventually overrun by Oda Nobunaga.