(The Turks are sending firefighting planes to Israel despite political problems. The US sends vaccine to Iran all the time. That got me thinking.)
At the height of WWII, not at the end when people were cutting deals, was there any case of Allied and Nazi governments cooperating on anything? Maybe meetings of the International Postal Union or something?
I believe there were POW exchanges during the war. And of course, there would have been a certain level of diplomatic communication - even with ambassadors recalled and war raging, countries still need to talk to one another.
On the other hand, despite countries not liking one another very much, Turkey is far from being at war with Israel, and the United States is (knock on wood) far from being at war with Iran.
All sorts of cooperation, at multiple levels, went on between the United States and the Soviet Union during the Cold War, but then, it was only a metaphorical war, not a real one.
I am pretty confident I saw a thread here a few weeks or months ago discussing trades of ammunition and war supplies between Allied and Axis powers during the war. That’s not simply private producers smuggling goods to enemy states for personal gain or because they wanted to support the other side’s cause but actually trades in war supplies among the governments, or at least military bureaucracies at a level below the central governments, bartering in goods.
In my mind’s eye, I sort of wonder if there were any meetings between US/British officers and Nazi officer, both in uniform. An idle question, but it would make a nice tense bit of a novel or something.
In 1941, Hitler’s deputy as head of the NSDAP, Rudolf Heß, flew from Germany to the UK, where he parachuted and was arrested. The most widely accepted version of what he was about to do was that it was a single-handed atzempt not previously discussed with Hitler, and that Heß was hoping he could negotiate a truce with the UK. However, there have always been, and are still, romours that Hitler had been in the know and that Heß had been sent by Hitler to negotiate a truce.
Another instance of alleged attempts by Hitler to appease the British during the war was the Dunkirk episode of 1940, when the British expeditionary force was trapped in Dunkirk with German troops advancing. Unexpectedly, the German advance came to a halt, which gave the British time to evacuate the forces back across the Channel. Rumours persist that Hitler himself had given the order to halt, hoping he could negotiate a truce with London. Maybe not quite face-to-face meetings of Nazi and British officers, but still an example (if these cases are true) of at least attempted cooperation.
Not precisely what you are looking for, but there were the Blood for Goods negotiations, concerning the exchange of Hungarian Jews for materials including trcuks for the SS and minerals including tungsten.
The US-USSR hotline was set up in cooperation after noticeable communication delays during the Cuban missile crisis.
And I believe that after reports reached the US about certain near-misses in Soviet military procedures, the US provided their military with information about how to structure military command & control procedures to minimize the possibility of errors in nuclear control systems. Some effort was spent on misdirection in this, to prevent the Soviets from realizing how the US knew about the near-misses, so as to avoid exposing US spies in the Soviet military system.
That’s not as far fetched as it sounds. In neutral countries like Switzerland, Sweden, Spain, or Argentina* diplomats from Allied and Axis powers would’ve moved in the same social circles, attended the same receptions, etc. This includes military attaches who’d naturally be wearing dress uniforms.
*Yes, I know Argentina did declare war, but not until final days of the war when Berlin was about to fall.
The Dunkirk retreat was carried out under heavy fire until the end, there were other units of the BEF trapped and fighting until they ran out of anything they could fight with like the 51st Highland Division and there were troops landing in other French ports further along the coast. It was when France capitulated that the total pullout happened. Churchill flew to France to shore up support when all this was going on. Didn’t work though, and I guess you are right that Hitler at that stage had other ideas.
I’m sure that the military attaches in Lisbon all knew each other. There were scheduled passenger flights to all sorts of places during the war, routed through Portugal, even if it was mostly diplomatic bags.
In the European theatre, the Germans and the western allies exchanged chronically ill/badly injured POWs (ie those who could no longer be used against them). I believe that each side shipped an equal number of the POWs to Sweden where they were exchanged. I’m reasonably sure that thousands of prisoners were exchanged that way.
A bit of diligent Googling should find you some further info on that if you’re interested.
To the best of my knowledge, nothing similar happened in the Pacific theatre or on the eastern front. It’s hard to imagine the Nazis & the Soviets co-operating like that, and I can’t see the Japanese doing it either.
Short term informal truces to collect wounded from the battlefield probably happened on all fronts, depending on the humanity of the field officers.
The Red Cross ship SS Vega was, after considerable negotiation, allowed to bring food parcels to the occupied Channel Islands in Dec 1944 where the population was undergoing considerable privations.