This week in 1944 saw the start of the breakout from prisoner-of-war camp Stalag Luft III by 76 inmates, an event that inspired the film, The Great Escape. But the regime endured by many PoWs was far harsher than that portrayed in the film, as the author of a new book reveals.

SO far we have seen the world of the prisoners of war held by the Germans very much through rose-tinted spectacles.

Blame excellent books like The Wooden Horse, the TV series Colditz and films like The Great Escape.

All good heroic material but what nobody has pointed out till now is that these were stories of prison camps for officers, not the common soldier, sailor or airman.

Here plucky chaps, well-fed, adequately housed and well-groomed, were perpetually trying to outwit the enemy and get back to join the war effort.

Now in Hitler's British Slaves, Sean Longden has come up with a less sanitised version of what happened elsewhere which makes the perceived version look like something "between a severe boarding school and a strict holiday camp".

The Third Reich was not famous for following the rules in general and of the Geneva Convention in particular but what is not widely known is that under Article 27 of the convention all able-bodied prisoners below the rank of corporal were obliged to work.

And boy did they work, in farms, factories and mines, sweeping streets, and clearing bombsites under conditions of unimaginable severity!

That was the fate of 200,000 British and Commonwealth servicemen captured between 1940 and the hapless defeat of the British Expeditionary Force and the war's end in 1945.

One mentioned in the book is George Marsden, of the Duke of Wellington's Regiment, captured in the Netherlands in 1944.

Another of the heroes of the book, Leslie Allan, founder of the National Ex-Prisoner of War Association, makes no bones about the fact that they were simply slaves.

"A slave is someone who is made to work under threat to his life. If a slave tries to run away he is killed.

"It was the same for us. We were given a bowl of soup and bread made from sawdust. It you didn't do as you were told you were shot."

That puts the matter into perspective.

In fact men who had often been marched hundreds of miles into captivity were worked on 12-hour shifts, seven days a week, on starvations rations often of watery soup and hard dry bread.

They were, says Sean, often dressed in the rags of a motley collection of uniforms and clogs that meant they could only shuffle along.

Conditions varied wildly from camp to camp. Not all lived in the wooden huts so familiar from the films. Some were in former army barracks or Hitler Youth camps, the unlucky lived in tents.

They were often distinguished by what they had not got - no bowls or eating utensils: perhaps use a tin hat instead; no guarantee of water supplies, nor soap, nor towels.

One of the perks of working outside the camps was the ability to pick up litter which could make up for the lack of toilet paper or to pick up cigarette ends which could be recycled for use.

Officially those working in industry were entitled to the same food and conditions as the local workers and 60% of the German pay - after a reduction for food and lodgings.

In practice thousands never received a penny in wages. And for those who did there were ingenious schemes for clawing it back again.

Some were indignant to find their pay was subject to income tax, others found they were expected to pay to hire a football pitch. Razor blades cost a month's wage and so few shaved more than once a week.

Toilet facilities were primitive and the men, literally lousy through lack of washing facilities, were also plagued by numerous insects.

In this condition, weak, enfeebled and disconsolate, they could often simply walk out of the camps - but in their conspicuous clothing were in no way equipped to find their way to freedom.

And, just when you thought you had it bad, think of those for who it was worse - the Russians for whom the Germans had a special hate, think of the black troops, the Indians, the Jews.

Some protested about having to work helping the German war effort - but if you persisted you were likely to be hit by a rifle butt if you were lucky, when you were unlucky it was a bullet in the head.

In all a desperate time that we need to remember - even the British government which has failed to recognise their claims for compensation, unlike those of PoWs in the Far East.

9 Hitler's British Slaves. Sean Longden/ Arris. £19.99