The Potsdam Conference was held between the 17 July and 2 August 1945 in the Cecilienhof, Potsdam and was the last of the "Big Three" meetings of WW2.
The main participants were American President Harry S. Truman, British Prime Minister Winston Churchill (and his successor, Clement Attlee) and Soviet Premier Joseph Stalin.
Churchill, Truman and Stalin at the Cecilienhof
President Roosevelt died on the 12th April 1945 and was replaced by Harry Truman
As the result of a General Election earlier in the month, on the 28th July 1945 Churchill was replaced by the new Prime Minister Clement Attlee
Where Yalta agreed on the principle that Germany was to be divied into four zones of occupation, Potsdam had the difficult task of defining these zones.
This involved the Americans falling back in some areas and the Soviets leaving the western districts of Berlin
The division of Germany into the four Zones of Occupation with the green arrows showing where the Americans pulled back from their forward positions
The four zones of Berlin.......the French were included but their districts had to come from UK or USA allocated areas
The yellow area of Wedding and Reinichendorf (Districts 7&20) were given to the French by the UK