War novel
Origins: The war novel's origins are in the epic poetry of the classical and medieval periods, especially Homer's The Iliad, Virgil's The Aeneid, sagas like the Old English Beowulf, and Arthurian literature. All of these epics were concerned with preserving the history or mythology of conflicts between different societies, while providing an accessible narrative that could reinforce the collective memory of a people.  Other important influences on the war novel included the tragedies of dramatists such as Euripides, Seneca the Younger, Christopher Marlowe, and Shakespeare. Euripides' The Trojan Women  is a powerfully disturbing play on the theme of war's horrors, apparently critical of Athenian imperialism. Shakespeare's Henry V, which focuses on events immediately before and after the Battle of Agincourt (1415) during the Hundred Years' War, provides a model for how the history, tactics, and ethics of war could be combined in an essentially fictional framework. Romances and satires in Early Modern Europe, like Edmund Spenser's epic poem The Faerie Queene and Miguel de Cervantes's novel Don Quixote, to name but two, also contain elements that influenced the later development of war novels. In terms of imagery and symbolism, many modern war novels (especially those espousing an anti-war viewpoint) are influenced by Dante's depiction of Hell in the Inferno, John Milton's account of the war in Heaven in Paradise Lost, and the Apocalypse as depicted in the biblical Book of Revelation. A Notable non-western example of war novel is Luo Guanzhong's Romance of the Three Kingdoms.
As the realistic form of the novel rose to prominence in the seventeenth century, the war novel began to develop its modern form, although most novels featuring war were picaresque satires rather than truly realistic portraits of war. An example of one such work is Hans Jakob Christoffel von Grimmelshausen's Simplicius Simplicissimus, a semi-autobiographical account of the Thirty Years' War.

19th century war novels: The war novel came of age during the nineteenth century, with works like Stendhal's The Charterhouse of Parma (1839), which features the Battle of Waterloo, Leo Tolstoy's War and Peace (1869), about the Napoleonic Wars in Russia, and Stephen Crane's The Red Badge of Courage (1895), which deals with the American Civil War. All of these works feature realistic depictions of major battles, scenes of wartime horror and atrocities, and significant insights into the nature of heroism and cowardice, as well as the exploration of moral questions.

World War I and World War II: World War I produced an unprecedented number of war novels, by writers from countries on all sides of the conflict. One of the first and most influential of these was the 1916 novel Le Feu (or Under Fire) by the French novelist and soldier Henri Barbusse. Barbusse's novel, with its open criticism of nationalist dogma and military incompetence, initiated the anti-war movement in literature that flourished after the war.
Of equal significance is the autobiographical work of Ernst Jünger, In Stahlgewittern (1920) (Storm of Steel). Distinctly different from novels like Barbusse's and later Erich Maria Remarque's Im Westen nichts Neues (All Quiet on the Western Front), Jünger instead writes of the war as a valiant hero who embraced combat and brotherhood in spite of the horror. The work not only provides for an under-represented perspective of the War, but it also gives insight into the German sentiment that they were never actually defeated in the First World War.
The post-1918 period produced a vast range of war novels, including such "home front" novels as Rebecca West's The Return of the Soldier (1918), about a shell shocked soldier's difficult re-integration into British society; Romain Rolland's Clérambault (1920), about a grieving father's enraged protest against French militarism; and John Dos Passos's Three Soldiers (1921), one of a relatively small number of American novels about the First World War. Also in the post–World War I period, the subject of war is dealt with in an increasing number of modernist novels, many of which were not "war novels" in the conventional sense, but which featured characters whose psychological trauma and alienation from society stemmed directly from wartime experiences. One example of this type of novel is Virginia Woolf's Mrs. Dalloway (1925)', in which a key subplot concerns the tortuous descent of a young veteran, Septimus Warren Smith, toward insanity and suicide. In 1924, Laurence Stallings published his autobiographical war novel, Plumes.
The 1920s saw the so-called "war book boom," during which many men who had fought during the war were finally ready to write openly and critically about their war experiences. In 1929, Erich Maria Remarque's Im Westen nichts Neues (All Quiet on the Western Front) was a massive, worldwide bestseller, not least for its brutally realistic account of the horrors of trench warfare from the perspective of a German infantryman. Less well known but equally shocking in its account of the horrors of trench warfare is the earlier Stratis Myrivilis' Greek novel Life in the Tomb, which was first published in serialised form in the weekly newspaper Kambana (April 1923 – January 1924), and then in revised and much expanded form in 1930. Also significant were Ernest Hemingway's A Farewell to Arms (1929), Richard Aldington's Death of a Hero (1929), Arnold Zweig's Der Streit um den Sergeanten Grischa (1927) (The Case of Sergeant Grischa), Charles Yale Harrison's Generals Die in Bed (1930). and William March's Company K (1933).

Novels about World War I appeared less in the 1930s, though during this decade historical novels about earlier wars became popular. Margaret Mitchell's Gone with the Wind (1936), which recalls the American Civil War, is an example of works of this trend. William Faulkner's The Unvanquished (1938) is his only novel that focuses on the Civil War years, but he deals with the subject of the long, aftermath of it in works like The Sound and the Fury (1929) and Absalom, Absalom! (1936).
The 1990s and early 21st century saw another resurgence of novels about the First World War, with Pat Barker's Regeneration Trilogy: Regeneration (1991), The Eye in the Door (1993), and The Ghost Road (1995), and Birdsong (1993) by English writer Sebastian Faulks, and more recently Three to a Loaf (2008) by Canadian Michael Goodspeed.

World War II: World War II gave rise to a new boom in contemporary war novels. Unlike World War I novels, a European-dominated genre, World War II novels were produced in the greatest numbers by American writers, who made war in the air, on the sea, and in key theatres such as the Pacific Ocean and Asia integral to the war novel. Among the most successful American war novels were Herman Wouk's The Caine Mutiny, James Jones's From Here to Eternity, and Hemingway's For Whom the Bell Tolls, the latter a novel set in the Spanish Civil War.
Jean-Paul Sartre's novel Troubled Sleep (1949) (originally translated as Iron in the Soul), the third part in the trilogy Les chemins de la liberté, The Roads to Freedom, "depicts the fall of France in 1940, and the anguished feelings of a group of Frenchmen whose pre-war apathy gives way to a consciousness of the dignity of individual resistance - to the German occupation and to fate in general - and solidarity with people similarly oppressed." The previous volume Le sursis (1945, The Reprieve, explores the ramifications of the appeasement pact that Great Britain and France signed with Nazi Germany in 1938. Another significant French war novel was Pierre Boulle's Le Pont de la rivière Kwaï (1952) (The Bridge over the River Kwai). He served as a secret agent under the name Peter John Rule and helped the resistance movement in China, Burma and French Indochina.  War is a constant and central theme of Claude Simon (1913 – 2005), the French novelist and the 1985 Nobel Laureate in Literature: "It is present in one form or another in almost all of Simon's published works, "Simon often contrasts various individuals' experiences of different historical conflicts in a single novel; World War I and the Second World War in L'Acacia (which also takes into account the impact of war on the widows of soldiers); the French Revolutionary Wars and the Second World War in Les Géorgiques." He served in the cavalry in 1940 and even took part in an attack on horseback against tanks. "The finest of all those novels is the one in which his own brief experience of warfare is used to tremendous effect: La Route Des Flandres (The Flanders Road, 1960) [...] There, war becomes a metaphor all too suitable for the human condition in general, as the forms and protocols of the social order dissolve into murderous chaos.'"