Final answer:
Stalin broke important Yalta Conference promises, including holding free elections in Poland and creating a coalition government, instead establishing a Communist government, and delayed committing to enter the war against Japan.
Step-by-step explanation:
The Yalta Conference between Roosevelt, Churchill, and Stalin in February 1945 resulted in several promises that were not fulfilled by Stalin. Two significant promises included free elections in Poland and the creation of a coalition government that represented democratic interests. Stalin had agreed to these terms but went on to install a government in Poland that was dominated by Communists, contradicting the principle of free elections. Additionally, Stalin promised at the Yalta Conference to enter the war against Japan following Germany's surrender, but the conditions he set forth such as U.S. recognition of Soviet claims in Asia exemplified the tension between the short-term objectives of war strategy and long-term geopolitical considerations.