Hunt based the book on the stories her grandfather told her about growing up in southern Illinois during the Civil War. Like the protagonist Jethro, Hunt's grandfather was nine years old when the Civil War began. To tell the story of the Creighton family, Hunt relied on family letters, records, and diaries as well as her own extensive research into the period. In her Author's Note, Hunt writes, "As to the story of the Creightons, there is hardly a page in this book on which a situation has not been suggested by family letters and records and by the stories told by my grandfather." She notes that her grandfather "gave his listeners a wealth of detail that enabled us to share with him the anxiety and sorrow of the times as well as the moments of happiness in a close-knit family." In "Books and the Learning Process," her Newbery Medal acceptance speech for her second novel, Up a Road Slowly, Hunt noted that Across Five Aprils presented "the issues, a way of life, and a tragic leaf of history."
Across Five Aprils differs from other Civil War novels in its treatment of the war. Critics have likened the novel to a Greek tragedy, in which the action occurs offstage and the characters discuss and reflect on these events.
