World War II

====Asia====
The [[Kuomintang]] (KMT) party in China launched a [[Northern Expedition|unification campaign]] against [[Warlord Era|regional warlords]] and nominally unified China in the mid-1920s, but was soon embroiled in [[Chinese Civil War|a civil war]] against its former [[Chinese Communist Party]] allies{{sfn|Preston|1998|p=104}} and [[Central Plains War|new regional warlords]]. In 1931, an [[Statism in Shōwa Japan|increasingly militaristic]] [[Empire of Japan]], which had long sought influence in China{{sfn|Myers|Peattie|1987|p=458}} as the first step of what its government saw as the country's [[Hakkō ichiu|right to rule Asia]], staged the [[Mukden incident]] as a pretext to [[Japanese invasion of Manchuria|invade Manchuria]] and establish the [[puppet state]] of [[Manchukuo]].{{sfn|Smith|Steadman|2004|p=28}}

China appealed to the [[League of Nations]] to stop the Japanese invasion of Manchuria. Japan withdrew from the League of Nations after being [[Lytton Report|condemned]] for its incursion into Manchuria. The two nations then fought several battles, in [[January 28 incident|Shanghai]], [[Battle of Rehe|Rehe]] and [[Defense of the Great Wall|Hebei]], until the [[Tanggu Truce]] was signed in 1933. Thereafter, Chinese volunteer forces continued the resistance to Japanese aggression in [[Pacification of Manchukuo|Manchuria]], and [[Actions in Inner Mongolia (1933–1936)|Chahar and Suiyuan]].<ref>{{Harvnb|Coogan|1993}}: "Although some Chinese troops in the Northeast managed to retreat south, others were trapped by the advancing Japanese Army and were faced with the choice of resistance in defiance of orders, or surrender. A few commanders submitted, receiving high office in the puppet government, but others took up arms against the invader. The forces they commanded were the first of the volunteer armies."</ref> After the 1936 [[Xi'an Incident]], the Kuomintang and communist forces agreed on a ceasefire to present [[Second United Front|a united front]] to oppose Japan.{{sfn|Busky|2002|p=10}}