After finishing her third novel, she sent the manuscript to two publishers and presented a copy to a Random House editor whom she had met at a writer's conference.
Her feudal Japan series, which eventually reached 16 titles, deals with the experiences of Sano Ichirō, a samurai and minor official who, by the end of the first novel, becomes the trusted chief investigator for the fifth Tokugawa shōgun, Tokugawa Tsunayoshi, and by the tenth novel, is promoted to a very high office.
Rowland takes some literary license with known figures, creating fictionalized versions of Tokugawa Tsunayoshi, Emperor Higashiyama in The Samurai's Wife, and Yanagisawa Yoshiyasu.
Sano is thus often at odds with the shōgun's primary advisor Yanagisawa Yoshiyasu, who views Ichirō as a potential threat to his power.
Throughout the stories, Sano constantly has to deal with the moral conflict of following the code of bushido while serving both justice and his master, the Shogun.
After his arranged marriage at the start of the fourth novel to Reiko, he also has to deal with her non-traditional attitude as she frequently involves herself in Sano's investigations.