At the end of the 19th century, the Qing Dynasty and Japan fought a Sino-Japanese War due to the Korean issue, which resulted in the accumulation of the Thirty Years of the Qing Dynasty being destroyed. After the defeat, daqing also began to become humble in the face of Japan. However, it was not until the "918 Incident" that Japan invaded the three northeastern provinces, and the Chinese people also began a fourteen-year war of resistance against Japan.
But in fact, we all know that Japan has not been idle for more than thirty years, and has focused its main energy on China. So how did Japan invade China during this period?
Japan had plans to invade China, and the northeast was the most important. At the beginning of the twentieth century, Japan and Russia fought a war in the northeast, the Qing government did not dare to offend, nor did they dare to speak much, after the war, Japan gained a lot of Russian rights and interests in the northeast, and also had a garrison in the northeast, and gained a foothold in the northeast.
Before and after the Xinhai Revolution, Japan attempted to split Northeast China, and even directly launched two independent movements to split Manchuria and Mongolia, which was also the first attempt of Manchukuo.
After the outbreak of World War I, Japan declared war on Germany and occupied most of Shandong by force, burning and looting along the way. After Japan took over Germany's rights and interests in Shandong, Japan proposed to Yuan Shikai the "Twenty-One Articles", demanding that the Beijing government recognize Japan's inheritance of all Germany's privileges in Shandong.
Of course, the "Twenty-One Articles" that Yuan Shikai accepted touched on all aspects of China, including the transformation of Shandong into a Japanese sphere of influence, the acquisition of special rights in southern Manchuria and eastern Inner Mongolia, and of course, the railway privileges and so on. Japan's conspiracy to turn Northeast China and Inner Mongolia into its own colonies can be described as deliberate.
At the same time, Japan also set up consulates and factories everywhere in China, which on the surface was also done by the Western powers, but unlike this, this was only a pretense, the purpose of which was to spy on political, military, and economic intelligence and prepare for a full-scale invasion of China. Next, Japan signed a military agreement with the Duan Qirui government on the joint defense of the Japanese and Chinese armies against the enemy, and began to continuously march to the northeast.
In short, through a series of acts of aggression against China, Japan has become Chinese mainland imperialist country with the largest colonial power, especially in the northeast region. Of course, in addition to the Kwantung Army in the northeast, the other part was the Chinese garrison in Beijing and Tianjin, which was stationed in China according to the provisions of the Xinugu Treaty. In addition, the Japanese Lend-Lease in Shanghai also housed Japanese Marines.
Of course, after all, Japan has just risen, and it has only entered the ranks of great powers through the Russo-Japanese War, but it does not mean that Japan can do whatever it wants, and there is no opponent in the world. After all, Japan is only a small island country, has been poor for too long, has been scarce in resources, and even encountered an economic crisis.
Although Japan was anxious to annex Northeast China and even launch an all-out war, it was unable to do so, so during the Beiyang period, it could only continue to prepare.
Since the Sino-Japanese War, China has been helpless in the face of Japan's gradual encroachment, especially during the Beiyang warlord period, Japan has not given up invading China, but has been preparing for an all-out war. Of course, during this period, the Western powers still fantasized about dividing up China, and Japan also took the opportunity to collude with the Western powers. However, because Japan is geographically closer to China, and its ambition to annex China is far stronger than that of the Western powers, during the Beiyang warlord period, Japan became the vanguard of the invasion of China, and even more became the main force invading China.