The First Sino-Japanese War (1 August 1894 – 17 April 1895) was fought between Qing Dynasty China and Meiji Japan, primarily over control of Korea. After more than six months of continuous successes by the Japanese army and naval forces, as well as the loss of the Chinese port of Weihaiwei, the Qing leadership sued for peace in February 1895.
Shortly thereafter, Russia and its allies France and Germany demanded that Japan return its newly won Liaodong Peninsula because they had territorial designs of their own in China. Soon after this Triple Intervention, Russia leased Liaodong’s major cities, Port Arthur and Dalian. This move angered the Japanese government and public, because the peninsula had been won at high cost by the Japanese military during the war. The situation gave rise to the slogan Gashin Shōtan (remember the humiliation and endure hardship to revenge), which kept the Triple Intervention in the popular consciousness and stoked a desire for revenge.
The Treaty of Shimonoseki was signed...on 17 April 1895...[ending] the Sino-Japanese war of 1894-1895 after the rapid defeat of China by Japan. The main provisions of the Treaty included the Chinese agreement to recognize the independence of Korea, to cede part of FengTien province, the Pescadores and Formosa (Taiwan) to Japan, and to pay a substantial war indemnity. The severity of the terms, and China's inability to resist, marked the first serious international consequences of the rise of Japan and the growing feebleness of the Japanese Empire.
When the new Chinese Government peace negotiator, Li Hung-chang, arrived in Shimonoseki on March 19, Japan had already captured Weihaiwei (February 2) and a Japanese fleet carrying 6,000 troops had already reached the vicinity of the Penghu Islands, waiting for an order to strike. The occupation of the Penghus was completed on March 26, while the peace negotiations were still in progress. When Li Hung-chang protested that Japan should not demand the cession of unoccupied Taiwa, Ito had merely to point out that Japan could occupy the island any day.
...the navy, with many of its leaders personally involved in the 1874 expedition to Taiwan, saw in the victory an opportunity to acquire that island, which it deemed important for the defense of Japan. It predicted that unless annexed by Japan now, the island would be taken by a Western Power a few years hence. Citing as an example the effectiveness with which the French used Taiwan and the Penghus to impose a naval blockade against southern China during the Sino-French War of 1884-85, the navy argued that the possession of Taiwan by a Western Power would be a serious threat to the safety of Okinawa and southwestern Japan.
21 November 1894: Japanese troops assault and capture Port Arthur (Lüshun), and carry out a massacre of Chinese inhabitants who have not fled. The Japanese soldiers [were] incensed by the display of mutilated bodies of their comrades by the Chinese. 4,000 people are killed.
The 23,000-man Huai Army built a series of over one hundred trenches and fortified positions along the heights for about ten miles either side of the town of Chiulien-cheng (modern Jiuliancheng), stretching roughly from Antung in the southwest to Hushan in the northeast.
...On the night of October 24, Japanese troops successfully built a pontoon bridge across the Yalu beneath Hushan and moved into position for an assault without being detected. The Japanese assaulted Hushan at 5:00 p.m. the next day. The fighting ended around 10:30 p.m., when the Chinese deserted the fortified position. The same night, Chinese troops to the west withdrew from their headquarters at Chiulien-cheng without putting up much resistance.
Both sides fought the Battle of the Yalu River to a standstill and sailors on both sides fought bravely and with all they had to give. The Japanese had better ships, better and larger supplies of ammunition and better officers. Evenly matched at the outset of the fight, the torpedo cruiser Tsi Yuen and the corvette Kwan Chia fled almost immediately without firing a shot, and the aging cruisers Chao Yung and Yang Wei went up in flames before they had time to do much of anything.
During the night the two Japanese columns drew a cordon around the Chinese forces, and at three o'clock on Sunday morning the attack was delivered simultaneously and with admirable precision...the entrenched troops suddenly found themselves exposed to attacks from the force they had fought during the day and from new forces of fresh troops of unknown numbers. The Chinese lines which were so strong in front, were found comparatively weak in the rear. The unsuspicious soldiers, taken completely by surprise, fell into panic and were cut down by hundreds. They were surrounded and at every point where they sought safety in flight they met the foe.
...Half an hour after the night attack opened, the splendid position of Pyongyang was in the possession of the Japanese. The Chinese sent up a white flag of surrender at 4:30 PM.
The Japanese force totaled 10,000. Under the plan made by the Commander in Chief Liet Gen and Viscount Nozu Michitsura, the Japanese would break up their army into four parts and surround Pyongyang. Three of the forces would make demonstrations of making a frontal assault, while another army, which had landed at Wonson (Gensan) on the east coast of Korea would surprise the Chinese from the rear .
When Korea’s monarchy became unstable in 1894 because of the Tonghak rebellion, the Korean government asked both China and Japan to send troops to protect the royal family. The Japanese got there first with more than 7,000 men and seized the palace on July 21, appointing a regent. That day the British provided three steamers to carry 1,200 Chinese troops along with three Chinese warships to Korea. Four days later the Japanese navy intercepted and sank the British-chartered steamer Kowshing, killing 950 Chinese soldiers. Japan also attacked Chinese forces at Yashan. China and Japan declared war on each other on August 1.
On previous occasions, diplomacy had always found a way out of the oft.-recurring difficulties between Japan and her neighbors, and this time also efforts at mediation were not lacking. But Japan was determined not to be trifled with. Korea was a buffer state between herself and a Power which her statesmen had long had reason to dread. Korea, well governed, might be a real protection : Korea, governed according to Chinese notions corrupted to suit Korean tastes, could only fall into hostile hands. The hour had come for Japan to secure for good her ascendancy in Korea, by showing how weak a reed China was to lean upon — diplomatic attempts failed, and Japan sent her ultimatum on July 19th 1894.
It was vital for Japan, in order to protect its own interests and security, to either annex Korea before it fell prey (or was annexed) to another power or to insure its effective independence by opening its resources and reforming its administration. As one Japanese statesman put it, Korea was "an arrow pointed at the heart of Japan". Japan felt that another power having a military presence on the Korean peninsula would have been detrimental to Japanese national security, and so Japan resolved to end the centuries-old Chinese suzerainty over Korea. Moreover, Japan realized that Korea’s coal and iron ore deposits would benefit Japan's increasingly-expanding industrial base.