Is March: The Difficult Journey from Innocence to Experience an essay, and is it a work of literary criticism?
The literary work titled March: The Difficult Journey from Innocence to Experience is a work of fiction, a novel, that is based on an earlier novel, Little Women, by Southern writer Louisa May Alcott, and it explores the life of John March, a character in Alcott's novel, while he is a Union soldier after the time at which Alcott's novel ends: in other words, March is a spin-off of Little Women.
A novel by definition cannot be a literary criticism. What a novel can be, as this one shows, is an accurate presentation of the historic, social, economic, and cultural conditions of the time and location in which the novel is set. March gives a vividly correct portrayal of conditions in the South during the Civil War and therefore can be used to confirm and expand solid history of the period.
A literary criticism, on the other hand, is by definition a work in which the elements of a work of literature, fiction or nonfiction (such as Wordsworth's "Preface to Lyrical Ballads"), are examined in minute detail relating to every aspect and part of literature from structure through to symbolism and authorial style and all the way over to audience reception--and everything in between. Literary criticism is based on deeply educated and scholarly analysis and thinking. The best place to find literary criticism is to ask your librarian to direct you to and guide you through the collected volumes of criticisms in the Reference section of your school and county libraries.