Leopold II’s poor standing among historians today is widely explained by the brutal colonial regime he personally controlled in the Congo and the resulting long-term harm to Congolese people and institutions. Key explanations you’ll commonly see in reputable scholarship:

• Systematic brutality and human rights abuses: The regime was marked by forced labor, mutilations, mass deaths, and a ruthlessly extractive economy centered on rubber and ivory, leading to immense suffering and a drastic population decline in the Congo. This is a central focus of historical assessments and documentaries [historical scholarship on the Congo Free State].
• Personal responsibility and governance style: Leopold II designed and maintained a private, profit-driven administration that prioritized wealth extraction over indigenous welfare, with little oversight by the Belgian state for many years. This has shaped historians’ judgments about his motives and leadership ethics.
• Structural consequences for the region: The Congo’s colonial infrastructure and institutions were built around extraction, not development or governance capacity, contributing to post-independence governance challenges and enduring underdevelopment. This context informs assessments of Leopold’s long-term impact beyond immediate atrocities.
• International scrutiny and popular campaigns: Reports by observers, journalists, and activists—most famously Edmund Dene Morel and Roger Casement—helped mobilize international criticism and led to public pressure that eventually pushed Belgium to take over the colony, reinforcing narratives of exploitation and impunity associated with Leopold’s rule.
• Legacy and memory in Belgium and abroad: The Leopold II era complicates national memory, with debates about reconciliation, restitution, and how to commemorate or acknowledge the victims. Some modern discussions emphasize a critical reckoning with this past.

If you’d like, I can tailor a brief, sourced overview for a paper or classroom presentation, including short read suggestions and a timeline of key events from 1885 (the Congo Free State establishment) through the early 1900s (international advocacy and Belgian taken over by the state) to the eventual exposure and reforms.