King Leopald had promised to treat the African subjects humanely.
Step-by-step explanation:
The practice of slavery and bonded labor that was being practiced in Belgian colonies was seen worldwide with abject horror.
The king had ordered mutational of the people who did not work properly and this had resulted in a reign of terror of officers who were desperate to show the results they were getting in the colonies.
The King had promised that such treatment would stop if he be given Congo but contrary to that it was only aggravated into the depths of the Congo colony.