1945年8月8日，苏联履行雅尔塔协议的有关规定，在结束对德战争三个月后，正式对日宣战．苏联的参战，改变了太平洋战争的格局，推进了中国抗日战争的进程，同时也影响了国共两党在东北的命运．一、苏联出兵东北的背景1、日本在太平洋战场垂死挣扎．1945年，第二次世界大战的局 August 8, 1945, the Soviet Union to fulfill the Yalta agreement of the relevant provisions, in the three months after the end of the war on Germany, Japan formally declared war on Japan. The war in the Soviet Union changed the pattern of the Pacific War and promoted the progress of the Anti-Japanese War in China. At the same time, it also affected the fate of the two parties in the Northeast. First, the background of the Soviet Union sent troops northeast 1, Japan dying in the Pacific battlefield. In 1945, the Bureau of World War II