How a misunderstanding between a British brigadier and US general led to disaster on a Korean battlefield

His men were outnumbered eight to one, stranded on every side by human waves of Chinese Communist infantry attackers at the height of the Korean war.

But when the British brigadier reported the position to his American superior in the United Nations joint command, he did so with classic and -as it turned out - lethal British understatement.

"Things are a bit sticky, sir," Brig Tom Brodie of the Gloucestershire Regiment told General Robert H Soule, intending to convey that they were in extreme difficulty.

But Gen Soule understood this to mean "We're having a bit of rough and tumble but we're holding the line". Oh good, the general decided, no need to reinforce or withdraw them, not yet anyway.

The upshot was one of the most famous, heroic and - according to a BBC2 documentary on April 20 - unnecessary last stands in military history: the ordeal of 600 men of the "Glorious Gloucesters" at the Imjin river almost exactly 50 years ago.

With no extra support promised, the colonel in charge of the Gloucesters fell back to a hill overlooking the river, where they made their stand. For four days, mostly without sleep, they held off 30,000 Chinese troops trying to surge across the river, killing 10,000 of them with Bren gun fire.

When they tried to withdraw, they were too late. More than 500 of them were captured and spent years in Chinese camps. Fifty-nine were killed or missing. Only 39 escaped. Two soldiers were awarded Victoria crosses for bravery.

Their feat was credited with saving Seoul, the south Korean capital, from capture. But yesterday the official historian of the war, General Sir Anthony Farrar-Hockley, said Seoul probably would not have been endangered if the men had been withdrawn earlier, and they would not have been cut off or captured.

Sir Anthony, now 77, a former Nato commander-in-chief, was himself captured at Imjin as a young adjutant to the Gloucesters. He said a US officer - unlike Brig Brodie - would have known how to make Gen Soule understand, by using the phrase "Sir, there is all hell breaking loose here".

Sir Anthony said: "The two nations spoke military [language] in a slightly different way. It's certainly a good example of the old saying about Britain and the US as two nations divided by a common language."

He discloses the episode in Forgotten Heroes: Korea Remembered, a programme of interviews with veterans to mark the 50th anniversary of Imjin.

The programme says: "Any hopes of relief were dashed by an American misunderstanding of British understatement."

Sir Anthony said he learned of the conversation from a number of sources while researching An Honourable Discharge, the second volume of his Cabinet Office history of the Korean war, published in 1995.

He said: "I don't think anyone should be hard on the brigadier. He was talking in battle, when they were clinging on by their fingertips. Nobody had time to think of the nuances of what they were saying."

The British 29th brigade, of which the Gloucesters were part, saw 400 die at Imjin. The horror of the slaughter, which began on April 22 1951, is caught in the survivors' stories. John Dyer of Twyford, Berkshire, then a 20-year-old national serviceman with the Royal Ulster Rifles, says in the documentary: "I had never seen so many soldiers in my life. The hillside was literally covered in them. If you've ever seen on a film when lemmings go over a cliff, it was just like that.

"Then we realised that we were into trouble. We wouldn't be human if we hadn't got scared - a mass of people rushing at you, bayonets fixed, grenades being thrown, shouting, screaming, because they used it as a fear tactic."

Geoff Costello of Ashtead, Surrey, who was fighting with a platoon, says: "Several of their assaults just broke up because you can imagine the force of five Bren guns, with one loose on the side. That's 150 rounds all in one spurt in the space of seconds. I saw an awful lot of dead Chinese."

Dennis Whybro of Chelmsford, Essex, who was with the King's Irish Royal Hussars, describes racing by tank uphill to try to rescue the Gloucesters. "It was more or less a death or glory sort of stunt."

Mr Dyer said the courageous Chinese foot soldiers fought almost suicidally when they saw survivors escaping on tanks.

"The tanks were going straight through them. And that's all I could hear, these people screaming, being crushed by the tanks as they went through them. Quite a horrible experience."

Only when the tank carrying him reached safety did Mr Dyer see the full horror of what had happened.

"It was a mess, just a mess. The sides of the tanks were covered in blood. All the tracks were full of limbs, it was a mess. It was a mess. So much so that we were taken off into the tents so that we wouldn't see any more of it. But it was a horrible mess."

When the survivors and ex-prisoners finally returned home, it was to a Britain still sick of the 1939-45 war and uninterested in their experiences.

One of them says: "It's unfair that so many men should be killed and so many men should go [to Korea] and fight and put their lives on the line fighting for the principles of the United Nations.

"But you can't help human nature, can you?"