The Fengtian clique's support from abroad was Japan, which had vested economic and political interests in the region dating from the end of the Russo-Japanese War and was interested in exploiting their region's largely-untapped natural resources. The Japanese Kwantung Army, based in the Kwantung Leased Territory, also had responsibility for safeguarding the South Manchurian Railway and so had troops stationed in Manchuria, providing material and logistical support for the Fengtian clique. The co-operation initially worked to the benefit of both parties.
Zhang provided security for the railroad and Japanese economic interests, suppressing Manchuria's endemic banditry problem and allowing extensive Japanese investments. The Imperial Japanese Army assisted Zhang in the two Zhili-Fengtian Wars, including the suppression of the anti-Fengtian uprising by General Guo Songling, a senior Fengtian clique leader. However, Zhang wanted Japan's aid only to consolidate and expand his territory, but Japan envisioned a future joint occupation of Manchuria with Zhang. After he had achieved his objectives, he tried to improve relations with the United States and the United Kingdom by allowing both countries open access to the trade, investment, and economic opportunities in Manchuria that he had allowed only to the Japanese.
That change in policy came while Japan was in the midst of a severe economic crisis from the 1923 Great Kantō earthquake and successive economic depressions, and it caused both alarm and irritation in the Kwantung Army leadership. The situation was further complicated by the success of the Northern Expedition, led by Chiang Kai-shek of the National Revolutionary Army, in which the Kuomintang successively defeated Sun Chuanfang, Wu Peifu, and other warlords of the Northern Faction and the Beijing government, controlled by Zhang Zuolin. The Nationalists appeared poised to restore their rule over Manchuria, which was still officially claimed as part of the Republic of China.
The Nationalists, the Communists, and other elements in the Northern Expedition were then supported by the Soviet Union, which had already installed puppet governments in nearby Mongolia and Tannu Tuva.
The Japanese thought that Manchuria falling under Soviet or Nationalist domination was strategically unacceptable, and Zhang Zuolin no longer appeared trustworthy as an ally capable of maintaining a de facto independent Manchuria. Japan needed a context to establish its effective control over Manchuria without combat or foreign intervention, and it believed splitting up the Fengtian clique by the replacement of Zhang with a more co-operative leader would do so.
Zhang Zuolin, Wade-Giles romanization Chang Tso-lin, courtesy name Yuting, byname Dashuai (“Great Marshal”), (born March 19, 1875, Haicheng, Fengtian [now Liaoning] province, China—died June 4, 1928, near Shenyang, Liaoning province), Chinese soldier and later a warlord who dominated Manchuria (now Northeast China) and parts of North China between 1913 and 1928. He maintained his power with the tacit support of the Japanese; in return, he granted them concessions in Manchuria.
Born into a peasant family, Zhang Zuolin enlisted in the Chinese army and fought in the Sino-Japanese War of 1894–95. After the war, he organized a self-defense militia in his native district, and in 1905 Zhang’s growing military unit was organized into a regiment by the governor of Fengtian province. By 1912 Zhang had risen to the command of a division, in 1916 he became the military governor of Fengtian, and in 1918 he was appointed inspector general of Manchuria’s three provinces. From then on he controlled Manchuria as a virtually autonomous state within the Chinese republic.
In 1920 Zhang began to try to expand his power southward into North China proper. By 1924 his position was strong enough for him to extend his control to Beijing, then the capital of the Chinese republic, where he established himself, assuming the powers of a military dictator.
Zhang’s ambitions were threatened by the armies of the Nationalist Party (Kuomintang), which in 1927 advanced into North China under the leadership of Chiang Kai-shek in an attempt to complete the unification of the country. Disheartened by military reverses, Zhang Zuolin ordered his troops to abandon Beijing to the advancing Nationalists. On June 4, 1928, his train was destroyed by a bomb planted by Japanese extremists who hoped that his death would provoke the Japanese army into occupying Manchuria. Zhang was seriously wounded in the attack and died later that day. His son Zhang Xueliang succeeded in command of his forces.
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