Answer: China
Explanation: Japan attacked China on July 7, 1937. The attack was preceded by an incident at the Marco Polo bridge, which turned out to be a battle. The conflict lasted until September 2, 1945, and during this conflict, China was assisted by the Soviet Union and the United States. This Chinese-Japanese war was the largest Asian war in the 20th century. Human casualties in this conflict are considered to be the majority of civil and military casualties in the Pacific War.