A Bridge Too Far is probably the most faithful big budget war epic of its era, and the reason is that Attenborough was adapting Cornelius Ryan's 1974 book, which was built out of hundreds of interviews with men who were actually there. Several of them, including John Frost, Roy Urquhart and Brian Horrocks, were consulted on the film. So the skeleton is real. The three division chain, the single road, the blown bridge at Son, the radios failing, the drop zones sited miles from the objective, Frost holding the north end of Arnhem bridge and nothing else, the Waal crossing in canvas boats, the resupply drifting down onto German held ground, the Polish brigade arriving late and on the wrong bank, the withdrawal across the Rhine in the rain. All of that happened, roughly in that order, roughly for those reasons. Some of the small details people assume are Hollywood are the real ones. Major Digby Tatham-Warter really did go into battle with an umbrella. Kate ter Horst really did turn her house into a dressing station and read psalms to dying men. The Dutch surgeon Spaander is real. The sergeant who pulls a pistol on a surgeon to get his officer operated on comes straight out of Ryan's interviews. The German commanders being competent, quick and professional rather than cartoonish is accurate and was unusual for the time. Where it drifts is mostly in emphasis and blame. The film is heavily invested in making Boy Browning the villain. The famous line about a bridge too far is presented as a warning Browning gave before the operation, and the sourcing for that is thin. Ryan got it late, second hand, and it may well have been said afterward if it was said at all. Browning's family, including Daphne du Maurier, were furious about the portrayal, and modern historians generally think he has been made to carry weight that belongs further up the chain. Montgomery barely appears in the film. The man whose plan it was, whose reputation it was meant to restore, and who later called it ninety percent successful, is essentially absent from the story of its failure. The intelligence officer who gets sidelined for warning about SS armor is a composite. In the film he is Major Fuller. In life it was Brian Urquhart, Browning's intelligence officer, no relation to the general, and he was packed off on medical leave for being insistent. The substance is accurate. The name and the scene are not. The film also inflates the German armor. Watching it you come away thinking two full SS panzer divisions were sitting at Arnhem waiting. They were badly chewed up formations refitting after Normandy, closer to battlegroups than divisions, with a limited number of running tanks. What actually killed the British was not mass but reaction speed. Bittrich had blocking units moving within hours. That is a more interesting and more damning fact than the one the film gives you, because it means the operation lost to improvisation rather than to a hidden army. XXX Corps comes off worst of anyone. The film leans hard on the image of Guards tanks halted and brewing tea while men die up the road, and that image has done real damage to the historical reputation of a corps that was taking casualties the whole way up a road it could not leave. The halt at Nijmegen after the Waal crossing is genuinely controversial and historians still argue it, but the film frames it as complacency rather than as a unit out of infantry, out of daylight and sitting on an exposed embankment. Likewise Gavin's decision to secure the Groesbeek heights before pushing into Nijmegen is never really explained, so the American delay looks like carelessness instead of a defensible call about his own flank. The biggest structural distortion is proportional. The film is about the bridge, and the bridge was over by Thursday. Most of 1st Airborne died in the Oosterbeek perimeter afterward, in a nine day battle that gets a fraction of the screen time. And the film ends with civilians walking out of the ruins, which is moving, but it skips what came next for them. The Hunger Winter killed roughly twenty thousand Dutch civilians north of the rivers who had been told liberation was days away. If you want the corrective reading, Middlebrook's Arnhem 1944 is the detailed operational account, Robert Kershaw's It Never Snows in September gives you the German side properly, and Beevor's Arnhem is the modern argument that the plan was unsound at conception rather than unlucky in execution. Ryan is still worth reading, just understand that he was writing a human mosaic, not an operational analysis, and the film inherited both the strength and the limitation of that.