Harriet Winslow
At the beginning of the novel, Harriet is an old woman who is recounting her memories of Mexico. She first went there to work as an English teacher, but became embroiled in the conflict between the old gringo and General Arroyo.
The old gringo
The old gringo is the protagonist of this novel and goes to Mexico seeking Pancho Villa. He is prepared to die for the revolutionary cause and offers to fight. He later meets Harriet and falls in love with her, leading to his death.
Arroyo
The old gringo is introduced to Arroyo in Mexico. Arroyo is a general who lets the old gringo join in the revolutionary effort.
La Luna
Arroyo's love interest.