Makers of history are at the mercy of their contemporary chroniclers. The “Dog Shogun” — his name proclaims it — was unfortunate in his.

Less hostile witnesses might have dubbed him the “compassionate shogun.” Even that would have been barbed praise — no praise at all. Compassion was no virtue in 17th-century Japan. It was unmanly, unwarlike. Peace was bad enough. Its first decades had at least left the lordly samurai their strutting, bullying martial swagger. Would the new shogun, with his “Laws of Compassion,” strip them even of that?

Tokugawa Tsunayoshi (1646-1709; ruled 1680-1709), broke the warrior mold. His commoner heritage via his low-born mother, his inherited sympathy for the suffering of the poor, his nonmilitary background, and his suppression of wanton killing and bullying as sportive assertions of class prerogative aroused resentment. The satire and invective it bred, accepted by later generations of historians as fact (argues at least one modern scholar), became the enduring classroom image of Tsunayoshi, the Dog Shogun, born in the Year of the Dog, whose compassion for dogs turned the beasts into masters and humans into their cringing servants.