Bartley's Man is about love, respect and honor, and becoming wealthy in the service of David Bartley, an up-timer teenager with a brilliant mind. It is the journey of Johan Kipper, a reluctant soldier in Tilly's tercio as he collides with the fact of Grantville's existence. Johan decides he doesn't want to be a soldier anymore. So he becomes what he thinks is a servant to entrepreneur David Bartley and the Higgins family.
They actually treat him like a person, in stark contrast to how he has been treated all his life by the royalty and nobility of his own time. Johan returns this genuine caring with love and loyalty as he watches David grow into manhood and he grows as a man.