Let's get back to brexit.

[vetran]

Both of these are myths.

Not quite there is some fact in them.

BBC - History - Britain retreats from France (pictures, video, facts & news)

British and French troops were left behind to defend the Dunkirk perimeter. They faced either death or an uncertain future as prisoners of war.

The British evacuation was also aided on 24 May by Hitler's surprising decision to halt their advance on Dunkirk for 48 hours.

He did halt it, the reasons are still being argued about.

[BlasterBates]

The reason Hitler stopped the advance was because some Generals believed the advance was too fast and that their troops were over-stretched. In hindsight this was mistake. Although Hitler did give the order, it was on the advice of a faction of Generals who had the feeling that some of the army was out of control. Rommel for example kept disobeying orders, charging ahead without waiting. It was basically Hitler trying to restore a bit of discipline to the invasion.

https://en.wikipedia.org/wiki/Battle_of_Dunkirk

In one of the most widely debated decisions of the war, the Germans halted their advance on Dunkirk. Contrary to popular belief, what became known as the "Halt Order" did not originate with Adolf Hitler. Field Marshals Gerd von Rundstedt and Günther von Kluge suggested that the German forces around the Dunkirk pocket should cease their advance on the port and consolidate, to avoid an Allied breakout. Hitler sanctioned the order on 24 May with the support of the Oberkommando der Wehrmacht (OKW).

[VectraMan]

No that is a bit of a myth, it was more a cock up, according to German documentaries, the German invasion went much quicker than anyone expected so there were tussles between Hitler and the Generals about slowing things down a bit.

I've seen that in documentaries too.

If you think about it, it would have been a huge and expensive undertaking for the Germans to take that many prisoners of war. Letting the men get away but leaving more or less all the equipment behind was perhaps a better outcome for the Wehrmacht.