Russian invasion of Manchuria Background . The Russian Empire long had designs on Manchuria as part of their Imperialist expansion across Eurasia . In the aftermath of the First Sino - Japanese War , Russia was alarmed at the rate in which Japan occupied Manchuria and achieved victory , leading the Russians to speed up their designs on Manchuria . With the building of the South Manchurian Railway , Mukden became a Russia n stronghold , which occupied it after the Boxer Rebellion . As with all other major powers in China , Russia demanded concessions along with the railroad . During the outbreak of the Boxer Rebellion Russia became involved due to its presence in the legations . Russian Cossacks participated in the Eight Nation Alliance relief forces during the Seymour and Gaselee expeditions , and Russian forces were present inside the legations during the sieges in Beijing and Tianjin . These forces were separate from the invasion of Manchuria , with the entire invasion exclusively directed by Russians . Campaign . The conflict was entirely bilateral , between Qing and Russian forces only . The Chinese forces in Manchuria were composed of the ethnic Manchu Eight Banners , and Han Chinese Boxers . Manchuria was also swarming with Han Chinese Honghuzi bandits , since the Qing rulers exiled Chinese criminals to Manchuria as a punishment . Chuang Guandong Edicts were posted by Boxers calling for attacks on Russian colonists and railroads in Manchuria . The Boxers attacked the South Manchurian railway and sought to destroy it . The Chinese treated Russian civilians leniently and allowed them to escape to Russia , even notifying them since a state of war existed , that they should leave the war zone , by contrast , Russian Cossacks killed civilians who tried to flee in the Chinese villages , westerners noted that the Chinese followed " civilized warfare " while the Russians massacred people . The Chinese summoned all available men to fight , and the Chinese forces and garrisons gathered artillery and bombarded Russian troops and towns across the Amur . Despite the Cossacks repulsing Chinese army crossings into Russia , the Chinese army troops increased the amount of artillery and kept up the bombardment . In revenge for the attacks on Chinese villages , Boxer troops burned Russian towns and almost annihilated a Russian force at Tieling . The Russians eventually cleared the river and crossed it for the invasion into Manchuria . 100 , 000 Russian troops participated in the invasion . The Russians invaded Manchuria during the rebellion , which was defended by Manchu bannermen . The bannermen were annihilated as they fought to the death against the Russians , each falling one at a time against a five pronged Russian invasion . The Russian historian Sergeĭ Mikhaĭlovich Shirokogorov reported that the Russians killed many of the Manchus , thousands of them fled south . The Cossacks looted their villages and property and then burnt them down . Manchuria was completely occupied after the fierce fighting that occurred . Aftermath . Sergei Witte advised the Czar to withdraw Russian forces from Manchuria , but Kuropatkin advocated for a continued Russian presence in Manchuria . The Russians tried to secure agreements favorable to themselves in exchange for withdrawal , but China refused . The Honghuzi continued to plague Manchuria despite multiple attempts aiming for their eradication and mass killings directed at them by Cossack forces . They were enlisted by the Japanese during the Russo - Japanese War to attack the Russians on their rear . Russo - Japanese War . Japan was angered that Russia had not withdrawn according to the treaty it signed in the Boxer Protocol in which it promised to withdrawal from Manchuria . The Chinese supported Japan during the war .