From 1885 to 1907, King Leopold II of Belgium had brutally seized the Congo for resources such as rubber, ivory, and precious metals. Leopold declared the Congo, the "Congo Free State" during its time of Belgian occupation. Rather than colonize the territory as other imperialist countries did, Leopold conquered and privately owned the entire region. His ownership of the land and its native people was determined by the United States and the European powers of the time (Cox). 

Leopold II brutally terrorized the Congolese. When Belgium was populating the area, they killed any natives that resisted the colonization, though most of the Congolese were docile. After the Congo Free State was established, the harvesting of rubber became priority for Leopold. Every native was forced to harvest and refine rubber for the Beligum kingdom. If a quota was not met, Leopold gave his administration orders to murder, humiliate, mutilate, and amputate men, women, and children (Britannica). This would be known as the "Rubber Terror." 

Cox, Mary-Lea. "Author Hochschild Recounts Lost History of Horror in the Belgian Congo." Wilson Center, https://www.wilsoncenter.org/article/author-hochschild-recounts-lost-his...

"Belgian Congo." Encyclopedia Britannica, https://www.britannica.com/place/Belgian-Congo.