At that time, with the German Army in retreat and Adolf Hitler's vision of a Nazi-controlled continent in tatters, Stalin, Roosevelt, and Churchill met at the Black Sea resort to decide how to occupy Germany and reorganize Europe into spheres of influence.
On Saturday, the grandsons countered the view that the U.S. and British leaders had underestimated Stalin's cunning and had abandoned Central and Eastern Europe to five decades of Soviet oppression -- starting the Cold War.
Winston S. Churchill III says that view is not consistent with the historic facts.
"People imagine that Churchill, Roosevelt, and Stalin arrived at Yalta with a blank sheet of paper to decide the fate of Europe. Nothing could be further from the truth. The fate of Europe have been decided several months before with the Red Army, probably a couple of hundred of Soviet divisions, sweeping westwards, rolling up the German Wehrmacht and taking over all the countries of Eastern and Central Europe. That was what decided the fate of Europe," Churchill said.
Even U.S President George W. Bush has condemned the Yalta conference -- saying in speeches that great nations had decided the destiny of smaller nations in a way that resulted in years of oppression.
Curtis Roosevelt, the grandson of U.S. wartime president Franklin D. Roosevelt, says Bush's remarks on Yalta are inaccurate and have left him angry.
"Misrepresentation, really the sense that Yalta is a bad word and the contempt for Yalta that is held by many people including my own President George Bush in his own speeches -- because I think it is quite irresponsible of him to make a kind of statements about Yalta that he has," Roosevelt said.
No other governments were allowed to send representatives to Yalta nor were they notified of decisions made at the meeting. Many historians view the interaction and personalities of Stalin, Roosevelt, and Churchill as decisive. They have criticized Roosevelt as too idealistic and Churchill as more interested in protecting Britain's colonial interests than the people of Eastern and Central Europe.
Earlier this year, Polish President Aleksander Kwasniewski described the Yalta conference as a "tragedy and a trauma."
For Eastern Europeans the end of World War II and Nazi occupation brought a new totalitarian ruler, the Soviet Union. Sixty years on this legacy still mars relations with Russia.
But the personalities of the three allied leaders of World War II loom large for their grandsons. Winston S. Churchill III still recalls a story told by his grandfather about Josef Stalin.
"My grandfather had a very nice phrase about [Josef Stalin]. He said: 'He's like a crocodile. You never know whether he is trying to smile or prepare to swallow you up,'" Churchill says.
Yevgeni Dzhugashvili, a military historian and former Soviet colonel, only learned that his grandfather was Stalin when he was 10 years old. He agreed that with a string of military victories, Stalin could feel comfortable and confident at Yalta.
"Churchill was very good in making up sayings and phrases, he is famous for it, but nevertheless, when Stalin got in the room, Churchill immediately stood up with his hands straightened up along his body, as if saluting an officer. I wonder why?" Dzhugashvili says.
Some historians say Stalin had refused to engage in a prisoner of war exchange -- an opportunity to trade a German military officer for his son, Dzhugashvili's father, who was captured by the Nazis during the war. Dzhugashvili continues to defend the Soviet war-time leader, saying such stories have not affected his views about Stalin.