Go Tell the Spartans is a 1978 American war film directed by Ted Post, starring Burt Lancaster, and based on Daniel Ford's 1967 novel Incident at Muc Wa, about U.S. Army military advisors during the early part of the Vietnam War in 1964, a time when Ford was a correspondent in Vietnam for The Nation.
The film's title is from Simonides's epitaph to the three hundred soldiers who died fighting Persian invaders at Thermopylae, Greece: "Go tell the Spartans, stranger passing by, that here, obedient to their laws, we lie."
Though the film had a limited release in the United States, critics, especially those opposed to the Vietnam War, praised it: "In sure, swift strokes," wrote Arthur Schlesinger, Jr. in the Saturday Review, "it shows the irrelevance of the American presence in Vietnam, the corruption wrought by that irrelevance, and the fortuity, cruelty, and waste of an irrelevant war." Stanley Kauffmann in The New Republic found it "the best film I've seen about the Vietnam War." More broadly, Roger Grooms in the Cincinnati Enquirer judged it to be "one of the noblest films, ever, about men in crisis."
(Summary from Wikipedia)