British prisoners of war were held in all theatres of war from 1940 to 1945. The British POW's held in German camps run by the military had a tolerable time as Nazi Germany was a signatory to the Geneva Convention and the Red Cross had reasonable access to German camps. Those held in Japanese POW camps in the Far East faced huge problems not experienced by their comrades in Germany and were kept in appalling conditions - and many died in these camps.
German POW camps were usually run fairly. As the men in these camps were from the military and German military personnel ran these camps, there was a degree of empathy between both sides. The British government had made it clear that they expected British POW's to try to escape and the Germans would have been well aware of this - especially as German POW's in Britain were also expected to do likewise. The delicate balance between captive and captor was only usually broken by an intervention by the SS or Gestapo. Cases of poor treatment of prisoners by the military staff at a German POW camp were rare, though they undoubtedly existed. So-called 'goon bating' was rare as it would only serve to antagonise those who worked in the camps and make life for the POW's even more difficult. The Red Cross was usually given good access to German POW camps and communication between families at home and POW's in Germany was as good as it could have been given the circumstances of war.
Those British POW's who were habitual escapees could be sent to Colditz - a POW camp touted by Goering as being escape-proof. It was British POW's at Colditz who came up with the idea of building a glider to escape - though the glider was not finished by the time the prison was liberated in April 1945.
Much has been written about the conditions for all POW's kept in Japanese POW camps. Japan had signed the Geneva Convention but its government had never ratified it, so technically Japan did not have to adhere to what was contained in the Convention.
The training for Japanese troops was brutal and effectively brutalised them even before they went into combat. The notion of not surrendering became implicit in this training as it dishonoured your family, your country and the emperor. This philosophy was beaten into each recruit and therefore the whole idea of surrender became abhorrent to a Japanese soldier. Therefore men who did surrender in combat were viewed on by the Japanese with disdain and contempt. Accordingly, these men deserved no better treatment than they got. To the Japanese, the British POW's they captured were to be used as they wished and many were worked to death. Disease and malnutrition were rampant in Japanese POW camps and many British POW's had reason to fear the brutality of their captors. At Changi POW camp, north of Singapore, medical treatment was organised by a Major McLeod. He was forbidden to use anaesthetics by the Japanese and had to carry out operations - including amputations - without the use of them. The most necessary of medicine was withheld by the Japanese - seemingly deliberately. To get around this at Changi POW camp, the POW's there made tablets that they convinced the guards would cure VD. These were sold to the guards and, in turn, the money was used to buy medicine from the men who had refused to give it out in the first place!
The Red Cross was faced with enormous difficulties in getting to these camps and inspecting them. All too often the necessary documents needed for a visit were not issued and, as an example, the Japanese did not even tell the Red Cross how many POW camps they ran. The Red Cross were told by the Japanese that there were 42 POW camps when there were over 100. Getting any type of communication back to Britain was made all but impossible by the Japanese, so that families in Britain had no idea as to what was going on with regards to their loved ones in the Far East. The Red Cross received a degree of criticism for this after the war, but given the circumstances they found themselves in (their Borneo delegate and his wife were shot for trying to get a list of prisoner names off of the Japanese) such criticism was harsh.
"British Prisoners of War". HistoryLearningSite.co.uk. 2011. Web.