High Seas wrote:
Oralloy - from contemporaneous sources you will see that informal talks were held between envoys of the Imperial Court of Japan and officials in Switzerland, Sweden, even Russia, BEFORE Potsdam - admittedly at low levels. When Japanese officials tried to meet higher-level Russians (with whom they were not at war at the time, as you know) they were allowed to arrive and then contemptuously told that the Russians had already left for Potsdam. The report of the returning delegation to Tokyo minutely describes the loss of face at this treatment - and that record, as well as many others, have been preserved by all participants. Secretary Stimson mentions it specifically in his diary - and he, unlike others in that administration, was extremely uneasy at dropping these terrible new weapons on what he called "defenseless women and children" in Japan.
Japan tried to talk to Russia about various topics throughout 1945.
Before the collapse of Germany, Japan tried to talk to Russia about making peace with Hitler. They thought that would allow Germany to focus all their resources on the western front, and force us to take resources away from the Pacific in order to shore up the UK.
After the collapse of Germany, Japan tried to talk with Russia about switching sides and helping Japan in the Pacific theater.
Around July of 1945, Japan gave up on "winning the war", and started thinking about "not losing the war". Then they tried to talk to Russia about mediating negotiations to end the war with a ceasefire (but only after we had been demoralized with the huge slaughter of our soldiers on Japan's beaches).
As you say, Russia was not much interested in talking with Japan. And since none of those attempts to talk to Russia amounted to a surrender attempt, we weren't much interested either.
The government of Japan did not engage with Switzerland or Sweden until after both A-bombs, when they actually started trying to surrender.