TERVUREN: When it comes to ruthless colonialism and racism, few historical figures are more notorious than Leopold II, the king of the Belgians who held Congo as his personal property and may have been responsible for the deaths of millions of Congolese more than a century ago.

Yet across Belgium, the monarch’s name is still found on streets and tunnels. Cities are dotted with his statues and busts, even as evidence of his misdeeds has piled up over the decades. Now a reckoning seems to be at hand.