The Greatest Battle (Italian: Il grande attacco, lit. 'The Great Attack') is a 1978 Euro War film co-written and directed by Umberto Lenzi and starring an all-star ensemble cast, including Giuliano Gemma, Helmut Berger, Stacy Keach, Ray Lovelock, Samantha Eggar, Henry Fonda, Evelyn Stewart and John Huston. The Italian-West German-Yugoslavian co-production was produced by Mino Loy and Luciano Martino for Titanus. It was also released under the titles The Biggest Battle and Battle Force.

The plot centers on a group of German and Allied nationals throughout the early years of World War II, including a British commando (Gemma), an American general (Fonda) and his son (Lovelock), a Jewish actress (Eggar), a war correspondent (Huston) and two very different German officers (Berger and Keach). The film climaxes in a recreation of the Battle of the Mareth Line in Tunisia.