All Our Yesterdays is divided chronologically and geographically. Part 1 describes the last school years and earliest adult experiences of the children of a middle-class provincial family in the late 1930’s. Part 2 takes Anna and her husband away to the southern village of San Costanzo. From their perspective the reader observes the impact of World War II on the family and on Italian society as a whole.

There is no single protagonist in the novel, which details the lives of the children of two neighboring families. Anna’s father, a widower, is an anti-Fascist who spends the last years of his life writing his memoirs, which will never be published. Anna’s sister, Concettina, is preoccupied with her boyfriends and eventually marries Emilio, arousing the political disapproval of several male members of the family. Anna meets Giuma, the youngest son of the family across the street, on the day of her father’s funeral. Giuma’s household consists of the old father who owns a local soap factory, his much younger wife, Mammina, Giuma’s elder brother, Emanuele, a rebellious sister, Amalia, and a mysterious German refugee, Franz, who is Mammina’s lover.

As Nazi Germany stands poised for the invasion of France, young Anna’s brother Ippolito, Emanuele, and their friend Danilo form a loose anti-Fascist group, whose program consists largely of reading clandestine newspapers behind closed doors. Ippolito becomes the first casualty of the war. Unable to accept the collapse of France and Italy’s collaboration with the Nazis, he shoots himself one morning on a park bench in the center of the town. His suicide coincides with Anna’s realization that she has been made pregnant by Giuma. She is sixteen years old. At this point an old family friend, Cenzo Rena, reappears. Learning of Anna’s crisis, he offers to marry her and takes her back to his home in the South.

The second half of the novel is much more than the chronicle of Anna’s marriage. It is a careful portrait of a time and place. Cenzo Rena is the self-appointed savior of the wretched village of San Costanzo, continuously campaigning for the basic standards of civilized life, such as regular health care for the women and children, and denouncing the doctor and schoolmistress for their ignorance, prejudice, and apathy. At first Anna, an outsider and still little more than a schoolgirl, feels completely alienated from this foreign and largely male-dominated society. Gradually, however, her eyes are opened to a new world which, while it offers her a spectacle of poverty and misery, also bestows on her the warmth and generosity of its people. She grows particularly close to La Maschiona, Cenzo Rena’s faithful housekeeper.

The war comes to San Costanzo with the arrival of a handful of Jewish refugees, a reminder of the special racial laws of 1938. Franz suddenly reappears, separated from his wife, Amalia, and rigid with the fear of captivity. Local sons and fathers are shipped overseas to fight for what is an increasingly losing cause. The village is finally occupied by retreating German troops in the summer of 1944. The occupation leads to inevitable tragedy when a “friendly” German soldier discovers Franz and other fugitives in Cenzo Rena’s cellar. There are reprisals, and Rena sacrifices himself to save the lives of innocent villagers.

Woven through these events is news of Anna’s family, conveyed by letter or visits. Her old governess, Signora Maria, is killed in an air raid on Turin. Her younger brother, Giustino, and his friend Danilo join the resistance. Emanuele edits a clandestine newspaper in Rome. Giuma turns up again, married to an American student of psychology. The war over, Anna returns with her daughter to the North to rejoin Giustino, Emanuele, and her family to face the future together, uncertain of what lies ahead and how to deal with the problems they will have to confront.