War historian Antony Beevor discussed that stereotype thusly:
''Patriotism also permeated those British war movies of the 1950s and 60s – The Dam Busters, Reach for the Sky, The Cruel Sea, The Heroes of Telemark, The Battle of the River Plate, Cockleshell Heroes. It camouflaged itself in self-deprecation, but the rousing march music in the finale always braced our belief in the rightness of our cause. We have long made fun of all the period cliches, unable to believe that anyone talked like that. But when researching my new book Arnhem: The Battle for the Bridges, I found that German officers really did say to the British paratroopers taken prisoner: “For you the war is over.” One of my favourite remarks, recorded at the time by a junior doctor, is the reaction of Colonel Marrable, the head of an improvised hospital in the Netherlands, when Waffen-SS panzergrenadiers seized the building. Still puffing gently on his pipe, he says to his medical staff: “Good show, chaps. Don’t take any notice of the Jerries. Carry on as if nothing has happened.” I have always been doubtful about the notion of “a national character”, but a national self-image certainly existed during the war and for some time afterwards.''
''Patriotism also permeated those British war movies of the 1950s and 60s – The Dam Busters, Reach for the Sky, The Cruel Sea, The Heroes of Telemark, The Battle of the River Plate, Cockleshell Heroes. It camouflaged itself in self-deprecation, but the rousing march music in the finale always braced our belief in the rightness of our cause. We have long made fun of all the period cliches, unable to believe that anyone talked like that. But when researching my new book Arnhem: The Battle for the Bridges, I found that German officers really did say to the British paratroopers taken prisoner: “For you the war is over.” One of my favourite remarks, recorded at the time by a junior doctor, is the reaction of Colonel Marrable, the head of an improvised hospital in the Netherlands, when Waffen-SS panzergrenadiers seized the building. Still puffing gently on his pipe, he says to his medical staff: “Good show, chaps. Don’t take any notice of the Jerries. Carry on as if nothing has happened.” I have always been doubtful about the notion of “a national character”, but a national self-image certainly existed during the war and for some time afterwards.''
https://www.theguardian.com/film/2018/may/29/antony-beevor-t...