California Yankee Under Three Flags takes place in Monterey, California during the four years before United States won the territory from Mexico in 1847. It is the story of an orphaned eighteen-year old girl, Emily Smith, who arrives in Monterey after sailing around the Horn from Boston and whose parents and brother have died of cholera on the voyage. The story unfolds as Emily moves from a position as governess with Consul Larkin’s children to a marriage with a ranchero. When Emily’s husband joins the insurgents who rid the territory of an unpopular Mexican governor, Emily becomes involved in the political events of the time and has to deal with the differences between the Californian and Yankee cultures. After her husband is killed she changes from being a girl uncertain of her abilities to a woman of strength and determination. The war between the United States and Mexico begins, and when the Yankees take over California also changes, from an easygoing pastoral society, to an aggressively materialistic one.