The Rosales Saga has five parts, all of them individual but interrelated novels, composed namely of the following titles in terms of historical chronology: Po-on, Tree, My Brother, My Executioner, The Pretenders, and Mass.

Their journey leads them to a new place at Rosales, Pangasinan, under the care of the wealthy mestizo named Don Jacinto, who despite owning large tracts of land, supports his fellow countrymen and indios in their plight.

[2][3][4][5][6][7][8][9] The events in Po-on happened from 1880s to early 1900s, when an Ilocano family abandoned their beloved barrio in order to overcome the challenges to their survival in southern Pangasinan in the Philippines, and also to flee from the cruelty they received from the Spaniards.

One of the principal characters of the novel is Eustaquio Salvador, a Filipino from the Ilocano stock who was fluent in Spanish and Latin, a talent he inherited from the teachings of an old parish priest named Jose Leon in Cabugao.

He lived in a period in Philippine history when a possible Filipino uprising against the Spanish government was about to erupt, a time after the execution of three mestizos, namely Mariano Gomez, José Apolonio Burgos, and Jacinto Zamora (or the Gomburza, an acronym for the three) at the erstwhile known Cavite (which is then renamed to Bagumbayan; now known as Rizal Park) on February 17, 1872.

The novel recreates the societal struggles in which the characters of Po-on were situated, which includes the protagonist Istak's personal search for life's meaning and for the true face of his beliefs at principles.