The term "epic" originally came from the poetic genre exemplified by such works as the Iliad, Epic of Gilgamesh, or the Odyssey. In classical literature, epics are considered works focused on deeds or journeys of heroes upon which the fate of a large number of people depend. Similarly, films described as "epic" typically take a historical character, or a mythic heroic figure. Common subjects of epics are royalty, gladiators, great military leaders, or leading personalities from various periods in world history. However, there are some films described as "epic" almost solely on the basis of their enormous scope and the sweeping panorama of their settings such as How the West Was Won or East of Eden that do not have the typical substance of classical epics but are directed in an epic style.
When described as "epic" because of content, an epic movie is often set during a time of war or other societal crisis, while usually covering a longer span of time sometimes throughout entire generations coming and passing away, in terms of both the events depicted and the running time of the film. Such films usually have a historical setting, although fantasy or science fiction settings have become common in recent decades. The central conflict of the film is usually seen as having far-reaching effects, often changing the course of history. The main characters' actions are often central to the resolution of the societal conflict.
In its classification of films by genre, the American Film Institute limits the genre to historical films such as Ben-Hur. However, film scholars such as Constantine Santas are willing to extend the label to science-fiction films such as 2001: A Space Odyssey and Star Wars. Lynn Ramey suggests that "Surely one of the hardest film genres to define is that of the "epic" film, encompassing such examples as Ben-Hur, Gone with the Wind....and more recently, 300 and the Star Wars films...none of these comes from literary epics per se, and there is little that links them with one another. Among those who espouse film genre studies, epic is one of the most despised and ignored genres" Finally, although the American Movie Channel formally defines epic films as historical films, they nonetheless state the epic film may be combined with the genre of science-fiction and cite Star Wars as an example.
Stylistically, films classed as epic usually employ spectacular settings and specially designed costumes, often accompanied by a sweeping musical score, and an ensemble cast of bankable stars. Epics are usually among the most expensive of films to produce. They often use on-location filming, authentic period costumes, and action scenes on a massive scale. Biographical films may be less lavish versions of this genre.
Many writers may refer to any film that is "long" (over two hours) as an epic, making the definition epic a matter of dispute, and raise questions as to whether it is a "genre" at all. As Roger Ebert put it, in his "Great Movies" article on Lawrence of Arabia:
The word epic in recent years has become synonymous with big budget B picture. What you realize watching Lawrence of Arabia is that the word epic refers not to the cost or the elaborate production, but to the size of the ideas and vision. Werner Herzog's Aguirre: The Wrath of God didn't cost as much as the catering in Pearl Harbor, but it is an epic, and Pearl Harbor is not.
The comedy film Monty Python and the Holy Grail had the joking tagline "Makes Ben-Hur look like an epic."