Why did King Leopold want to create overseas colonies?
Generally, King Leopold believed that colonial expansion was key to building a powerful state, and so he sought colonies for Belgium around the world. That said, Leopold set up Belgium's only colony in Africa not as an extension of a Belgian empire, but rather to add to his own personal fortune. Leopold formed a private company in 1876, with the stated goal of setting up a colony in the Congo region. After getting his claims recognized by the rest of Europe, he ruled the region as his own private domain, even using a private military force to enforce his will. He used brutal force to extract wealth from the natives of the region, first using native labor to obtain ivory and then rubber, which proved to be more profitable. Natives were worked under appalling conditions, facing death or mutilation if they failed to gather the required quotas of rubber.
The resulting death toll for the Congolese people was in the millions, and King Leopold faced global criticism for his policies, which were viewed by many as a case study in the abuses of imperialism, though Leopold's abuses were not on behalf of the kingdom he ruled, but for his own private gain. Like many imperialists, though, Leopold defended his actions by claiming, implausibly, that he had "undertaken the work in Congo in the interest of civilization and for the good of Belgium."