Van Reybrouck’s bibliography alone is worth the cover price. But what distinguishes the book is its clearheadedness. He patiently reminds us that Congo will always be a case apart because of its wealth. From Congo have come the materials of modernity: rubber for tires, copper and iron for industry, diamonds, uranium for nuclear warheads, coltan for cellphones. No hacking at the rock in Congo, no freeway, no Hiroshima, no iPhone. Washington think tanks are obsessed with Afghanistan, that other plummeting state, but Afghanistan looks like a distraction in planetary terms compared with what Congo is and what it becomes, what is kept alive there and what is dug up there.

Scientists say the Congolese rain forest must survive if we are to temper our climate. Equally important is to preserve the genetic diversity of microbial, plant and animal life on which Congo’s future wealth will depend. Congo’s mineral resources are unmatched — China is in Africa for Congolese ore. The Congo River provides unceasing freshwater and hydroelectric potential. Then there is us. There were 15 million Congolese at independence from Belgium in 1960. There are 71 million now. There will be an estimated 150 million before the middle of the century. Kinshasa is projected by then to be bigger than New York and Chicago combined.

Van Reybrouck skips a smooth stone across the deepness of days that form Congolese prehistory. We fast-forward through seasonal expeditions for catfish on streams flowing into the Great Lakes to the capture of Pygmies in the rain forest by ancient Egyptians and their journey up the Nile to dance for the Pharaohs. Plantain was introduced, more plentiful than yams, and its greenery did not draw the malarial mosquito. At some point drumming was invented. Drummers were capable of sending complex messages 370 miles in a day. Most people died where they were born. Then the Portuguese incursions on the Atlantic coast began. They left Catholic kingdoms. Maize was introduced, intensifying farming and trade. Slaves were hauled out. Four million Congolese were shipped to the Americas — 30 percent of the Atlantic slave trade. Ivory from forest elephants went along as well, to be turned into billiard balls in the industrial north. The deep memory of the Congolese was powerful beyond words then, but it went unrecorded. We can track languages, music, genes and pathogens, but monuments were grass, and artifacts were skins; there was no writing.

The recorded history is short, dramatic and one-sided. Whatever Congo had was fed into the maw of the world — and the world was indifferent. In 1874, The New York Herald and The Daily Telegraph of London financed Henry Morton Stanley, a Welsh explorer and journalist, to travel the length of the Congo River. Stanley arrived at the Atlantic in 1877. He was taken on the payroll of King Leopold II of Belgium, whose ministate had been created in 1830 as a buffer between France and Prussia. Leopold wanted a large slice of Africa and got it the Belgian way: Congo would be a free trade buffer between other colonial interests. Some villagers rose against the whites because they were white as bones; they must have come from the land of the dead. (Echoes of that feeling persist.) Traders and missionaries followed in Stanley’s footsteps. A third of the early Baptist missionaries died in the field. It was the Catholics who mostly won out. Catholic schools, Scout troops and sports clubs provided the basis of the Congolese elite.

Leopold’s bet paid off. John Boyd Dunlop’s invention of the inflatable rubber tire created a demand for Congolese rubber. The profits went to build Belgium at the cost of Congolese lives. Murder was casual. Since bullets were in short supply, there was a habit of cutting off the hands of those who had been shot as proof a bullet had been used to shoot a person and not an animal. It was worse than slavery: “For while an owner took care of his slave, . . . Leopold’s rubber policies by definition had no regard for the individual.” It would be absurd to talk of genocide or a holocaust, Van Reybrouck says, “but it was definitely a hecatomb.”