Esperanza Ortega is the main character in the novel "Esperanza Rising" by Pam Muñoz Ryan. She is a young girl from a wealthy family in Aguascalientes, Mexico, who experiences a dramatic change in her life when her father is killed. This event forces her and her mother to flee to the United States during the Great Depression. In the U.S., Esperanza faces numerous challenges as they become migrant workers in California. Throughout her journey, she learns about resilience, hope, and the importance of family. The story highlights themes of social class, identity, and the immigrant experience.