War film
William A. Wellman's Wings (1927) showed aerial combat during the war and was made in cooperation with the Army Air Corps. It proved a powerful recruiting tool. It became the first film (in any genre) to be awarded an Oscar for best picture. Later films of varied genres that deal with the First World War include David Lean's "colossal epic", both war film and biopic Lawrence of Arabia (1962), shot in the then unfamiliar and exciting 70mm Technicolor, and described by Steven Spielberg as "maybe the greatest screenplay ever written for the motion-picture medium"; Richard Attenborough's satirical anti-war musical comedy based on Joan Littlewood's play of the same name, Oh! What a Lovely War (1969); Spielberg's 2011 war drama War Horse was based on Michael Morpurgo's children's novel of the same name.
Many of the films promoted as "documentaries" added context to authentic battlefield scenes by staging critical events, and invented episodes and dialog to enhance excitement at the cost of authenticity.

Finnish Civil War: Although the 1918 Finnish Civil War between Whites and Reds remained a controversial topic a century later in Finland, many Finnish filmmakers have taken up the subject, often basing their work on a book. In 1957, Toivo Särkkä's 1918, based on Jarl Hemmer's play and novel, was screened at the 7th Berlin International Film Festival. Recent films include Lauri Törhönen's 2007 The Border, and Aku Louhimies's 2008 Tears of April, based on Leena Lander's novel. Perhaps the most famous film about the Finnish Civil War is Edvin Laine's 1968 Here, Beneath the North Star, based on the first two books of Väinö Linna's Under the North Star trilogy; it describing the civil war from the losing side, Finland's Red Guards.

Spanish Civil War: The Spanish Civil War has attracted directors from different countries. Sam Wood's For Whom the Bell Tolls (1943), based on Ernest Hemingway's book of the same name, portrays the fated romance between an American played by Gary Cooper and a partisan played by Ingrid Bergman against the backdrop of the civil war. The epic 168-minute film with its landscapes shot in Technicolor and a "beautiful" orchestral score was a success both with audiences and with critics. Alain Resnais's Guernica (1950) uses Picasso's 1937 painting of the same name to protest against war. Carlos Saura's La Caza (The Hunt, 1966) uses the metaphor of hunting to criticise the aggressiveness of Spanish fascism. It won the Silver Bear for Best Director at the 16th Berlin International Film Festival in 1966. Ken Loach's Land and Freedom (Tierra y Libertad, 1995), loosely based on George Orwell's Homage to Catalonia, follows a British communist through the war to reveal the painful contradictions within the anti-fascist Republican side.

Korean War: Samuel Fuller's The Steel Helmet (1951) was made during the Korean War (1950–1953). The critic Guy Westwell notes that it questioned the conduct of the war, as did later films like The Bridges at Toko-Ri (1954) and Pork Chop Hill (1959). Fuller agreed that all his films were anti-war. No Hollywood films about the Korean War did well at the box office; the historian Lary May suggested in 2001 that they reminded American viewers of "the only war we have lost".
In 1955, after the fighting, the successful South Korean action film Piagol  about leftist guerrilla atrocities encouraged other film-makers. The 1960s military government punished pro-communist film-makers and gave Grand Bell Awards to films with the strongest anti-communist message. The Taebaek Mountains (1994) dealt with leftists from the south who fought for the communists, while Silver Stallion (1991) and Spring in My Hometown (1998) showed the destructive impact of American military presence on village life. The violent action films Shiri (1999) and Joint Security Area (2000) presented North Korea in a favourable light.
Films in North Korea were made by government film studios and had clear political messages. The first was My Home Village (1949), on the liberation of Korea from the Japanese, presented as the work of Kim Il Sung without help from the Americans. Similarly, the country's films about the Korean War show victory without help from the Chinese. The film scholar Johannes Schönherr concludes that the purpose of these films is "to portray North Korea as a country under siege", and that since the U.S. and its "puppet" South Korea invaded the North once, they would do so again.

Algerian War: Gillo Pontecorvo's dramatic The Battle of Algiers ((Italian: La battaglia di Algeri; Arabic: معركة الجزائر; French: La Bataille d'Alger), 1966) portrayed events in the Algerian War (1954–1956). It was shot on location as an Italo-Algerian co-production. It had the black and white newsreel style of Italian neorealism, and even-handedly depicts violence on both sides. It won various awards including Golden Lion at the Venice Film Festival. It was attacked by French critics and was for five years banned in France as well as Jamila, the Algerian (1958).

Vietnam War: Few films before the late 1970s about the Vietnam War actually depicted combat; exceptions include The Green Berets (1968). Critics such as Basinger explain that Hollywood avoided the subject because of opposition to United States involvement in the Vietnam War, making the subject divisive; in addition, the film industry was in crisis, and the army did not wish to assist in making anti-war films.
From the late 1970s, independently financed and produced films showed Hollywood that Vietnam could be treated in film. Successful but very different portrayals of the war in which America had been defeated included Michael Cimino's The Deer Hunter (1978), and Francis Ford Coppola's Apocalypse Now (1979).  With the shift in American politics to the right in the 1980s, military success could again be shown in films such as Oliver Stone's Platoon (1986), Stanley Kubrick's Full Metal Jacket (1987) and John Irvin's Hamburger Hill (1987).
The Vietnamese director Nguyễn Hồng Sến's The Abandoned Field: Free Fire Zone (Cánh đồng hoang, 1979) gives an "unnerving and compelling .. subjective-camera-eye-view" of life under helicopter fire in the Mekong Delta during the Vietnam War. The film cuts to an (American) "helicopter-eye view", contrasting painfully with the human tenderness seen earlier.

Later wars: Dino Mustafić's Remake (2003), written by Zlatko Topčić, tells the parallel coming-of-age stories of a father living in Sarajevo during World War II and his son living through the Siege of Sarajevo during the Bosnian War. According to Topčić, the story is based on incidents from his own life.
The Iraq War served as the background story of U.S. movies, like The Hurt Locker from 2008, Green Zone from 2010, and American Sniper from 2014.
The War in Afghanistan since 2001 was depicted in various movies, among them Restrepo in 2010 and Lone Survivor from 2013.

Second World War: 

Made by Western Allies: The first popular Allied war films made during the Second World War came from Britain and combined the functions of documentary and propaganda. Films such as The Lion Has Wings and Target for Tonight were made under the control of the Films Division of the Ministry of Information. The British film industry began to combine documentary techniques with fictional stories in films like Noël Coward and David Lean's In Which We Serve (1942)—"the most successful British film of the war years"—Millions Like Us (1943), and The Way Ahead (1944).

In America, documentaries were produced in various ways: General Marshall commissioned the Why We Fight propaganda series from Frank Capra; the War Department's Information-Education Division started out making training films for the U.S. Air Force and U.S. Navy; the Army made its own through the U.S. Signal Corps, including John Huston's The Battle of San Pietro. Hollywood made films with propaganda messages about America's allies, such as Mrs. Miniver (1942), which portrayed a British family on the home front; Edge of Darkness (1943) showed Norwegian resistance fighters, and The North Star (1943) showed the Soviet Union and its Communist Party. Towards the end of the war popular books provided higher quality and more serious stories for films such as Guadalcanal Diary (1943), Mervyn LeRoy's Thirty Seconds Over Tokyo (1944), and John Ford's They Were Expendable (1945).

The Soviet Union, too, appreciated the propaganda value of film, to publicise both victories and German atrocities.