Children of a Northern Kingdom relates the story of a group of non-polygamous Mormons who flee to the north when their prophet and leader, Joseph Smith Jr., is assassinated in 1844. Leaving their city of Nauvoo in Illinois, they make their way to Voree, Wisconsin, where a man named James Strang has declared himself their new prophet.
Rusty Manning, a blacksmith, is part of this group, along with his wife Marie. Marie’s brother, Gabriel Romain, a physician, is the leader and driving force behind the group of friends. He gets them north to Wisconsin and eventually to Beaver Island in Lake Michigan, where they hope to be safe at last from persecution.
Their years on the island, where James Strang proclaims himself king and begins to practice plural marriage, their trials and persecutions, and their unsuccessful attempts to pacify their neighbors are depicted and described. Unable to leave the island without abandoning all their material possessions, they are eventually driven out by the non-Mormons when Strang is assassinated.
They are put on boats, with some separated from their families, and dispersed all along the Michigan and Wisconsin shorelines. The persecution and treatment of these Beaver Island Mormons is considered by most historians to be one of the darkest periods in Michigan history.
How Rusty, separated from his wife and his family, finally manages to reunite with them is an integral part of the story.