On 1587 after his father surrendered to Toyotomi Hidenaga at Taka Castle, he was given over as a hostage to Hidenaga. He then fought as a retainer for the Shimazu clan during the Seven-Year War and the 1600 battle of Sekigahara. He also had killed Ijuin Tadazane, a fellow Shimazu retainer, to put down a potential rebellion. He was considered an important retainer and became a Karō, a samurai official/adviser. During peacetime, Yamada took up the teaching of retainers as well as developing industries.
Yamada served in the shogunate army at the 1637-38 Shimabara Rebellion, a revolt involving mostly Japanese peasants, most of them Catholics.