In the 1950s in Kenya, British settlers lived in terror of an “evil” that was sweeping the country, threatening to wipe out their aristocratic enclave: Mau Mau. In reports to the Home Office, colonial authorities described a satanic primitive religion that was turning previously content and compliant servants and laborers into bloodthirsty butchers wreaking havoc across the land.

But for Africans, Mau Mau was the sound of liberation. Although there’s no expert consensus on its origins, a Ugandan writer I know who spent twelve years in Kenya tells me that in Kiswahili, Mau Mau is recognized as an acronym: it means “British go back to Europe; African gets Freedom.” As a child, he and his friends would whisper it at baffled white visitors.

Whatever its origins, Mau Mau was a cry of political rebellion. And it was the inevitable outgrowth of a half-century of repressive rule by the British in Kenya. By the 1950s, the British “civilizing” mission had ejected Kenyans from their land, destroyed their communities and transformed them into squatters, tenant farmers or low-wage laborers. It’s hardly surprising that some of those Africans had grown restive, and that most thought it was time for the British to go home. But for the British, the sinister pall cast over Mau Mau served an important purpose: It justified the hidden torture and brutality they used to retain their grip on power long after the myth of benevolent empire could possibly be sustained.

Two new books–Caroline Elkins’s Imperial Reckoning: The Untold Story of Britain’s Gulag in Kenya and David Anderson’s Histories of the Hanged: The Dirty War in Kenya and the End of Empire–cast the notorious Mau Mau uprising and the British response in a new light, revealing the astonishing lengths to which the British went to forestall the inevitable demise of their imperial enterprise.

Most Mau Mau leaders were drawn from the ranks of the Kikuyu, one of Kenya’s leading tribes. The Kikuyu had long been the country’s most prosperous farmers, until the British arrived in the late nineteenth century and white settlers began to appropriate their most fertile lands. Over time, the Kikuyu were forced onto tiny “reserves” that couldn’t possibly sustain them. The lucky ones were allowed to squat on settlers’ farms but were forbidden from growing the most profitable crops or owning more than a paltry amount of cattle. Mechanization and a rapidly intensifying land grab soon drove many off even these meager plots.

Recognizing that the deteriorating situation could explode, the British named Kikuyu “chiefs” to lord over their neighbors, handing them power, money and arable land in return for their loyalty. Chiefs enforced the colonial government’s strict tax laws and rules requiring all Kikuyu to carry identification and employment cards. So as African nationalism fostered calls for decolonization across Africa in the 1950s, it’s no wonder that in Kenya, where Africans were denied even the vote, those with the least land, education and prospects decided to take matters into their own hands. Reviving an old Kikuyu solidarity oath, they added a commitment to band together to eject the British and win their freedom.

The picture the British have painted of Mau Mau is one of striking brutality, of men who, via magical oath-taking ceremonies, were transformed into monsters who hacked their victims to pieces and displayed the remains for all to see. No doubt, many of the murders were gruesome and spread understandable alarm among Kenya’s white elite. But the image of Mau Mau has also overshadowed its reality: During the eight-year war, Mau Mau warriors killed only thirty-two European civilians and fewer than 200 British soldiers and police. Mau Mau violence was far more lethal to the Kikuyu who refused to join the cause: Mau Mau assassinated close to 2,000 Kikuyu civilians. Far from representing all Kikuyu, the movement began as a militant fringe, its terror tactics against its fellow tribesmen a response to the hierarchies the British themselves had created. But it is the British response to Mau Mau, which likely left more than 20,000 Africans dead (there is still no accurate count), that will most shock readers familiar with the official story.

This is the focus of Elkins’s Imperial Reckoning, which provides a painfully thorough catalogue of previously unknown atrocities by the British. Elkins, an assistant professor of history at Harvard, says she began her project expecting to tell a British success story. But after a decade combing through British archives and interviewing some 300 survivors of the war, she discovered that what had long been depicted as a laudable withdrawal and “rehabilitation” by the British was actually a cover-up of unimaginable proportions.

In 1952, a week after one of Mau Mau’s more notorious strikes–the murder of a prominent chief by attackers dressed as policemen–the British declared a state of emergency and rounded up prominent Kikuyu leaders, including Jomo Kenyatta, who would later become Kenya’s first president. Although Kenyatta was a widely respected leader of a moderate Kikuyu-led political party, the British deemed all Kikuyu suspect and so assumed Kenyatta was leading the Mau Mau revolt. His subsequent show trial and seven years’ imprisonment removed a prominent voice of progressive reform and created a rallying symbol for the radicals’ cause.

This was indicative of the course of the war. Instead of understanding Mau Mau as a radical movement among a population with legitimate political grievances, alarmed white settlers viewed each Mau Mau attack as a sign that an inhuman viciousness had seized the entire Kikuyu population. Their smiling servants had inexplicably become violent savages.

As the hysteria mounted after each attack, the British imposed harsher and harsher emergency measures. Thousands of suspected Kikuyu were rounded up, interrogated, beaten and humiliated, detained without charge, denied access to the evidence against them, convicted merely for suspected association with Mau Mau, and–since the British never declared the conflict a real war–denied the rights of prisoners of war under the Geneva Conventions. Reports of abuse and human rights violations from the International Committee of the Red Cross were ignored, as were complaints from representatives of the opposition party in London.

It all sounds eerily familiar: The British colonial government believed it was under siege from “evil”–an incomprehensible force beyond its control. There were meager attempts to win the “hearts and minds” of the Kikuyu behind barbed wire. The renowned archeologist and ethnographer Louis Leakey insisted Mau Mau must “confess” their oath and take a counter-oath to cure them of its powers. But any real attempts at “rehabilitation” of Mau Mau were quickly overwhelmed by the deprivation and brutality employed to extract confessions.

Not surprisingly, the British actions only drove more into the Mau Mau fold. Under the banner of a state of emergency, the colonial administration imprisoned innocents and punished entire villages when terrified residents refused to testify against their neighbors. Fearful settlers fired their Kikuyu laborers and ejected squatting farmers. And the administration closed Kikuyu schools, leaving more newly idle and angry Kikuyu with nothing to do but join the rebels.

Although tens of thousands were imprisoned without trial, some suspected Mau Mau were arrested, charged and tried for their alleged crimes. But as David Anderson, a lecturer in African studies at Oxford University, reveals in a vivid and comprehensive new account of the war, Histories of the Hanged, the trials testify as much to the brutality of the British counteroffensive as to the Mau Mau crimes themselves. Anderson, whose book is based largely on the documentation of 800 capital cases of accused Mau Mau that survive in the British archives, acknowledges the huge challenge the British faced trying to uphold justice when terrified witnesses recanted their testimony and the courts were overwhelmed with the volume of cases. But he also finds strong evidence of severe brutality by police against prisoners in 80 percent of those cases. The pressure to convict led to a complete abandonment of the most basic British principles of justice. More than a thousand men were sent to the gallows as convicted Mau Mau terrorists, many on the flimsiest of evidence. “In no other place, and at no other time in the history of British imperialism,” writes Anderson, “was state execution used on such a scale as this.”

What happened at the settlement at Lari was emblematic. One night in March 1953, the British-trained African vigilante force known as the Home Guard came upon the mutilated remains of a Kikuyu loyalist nailed to a tree. Then, they noticed fires breaking out in the direction of their own homes back in town. They raced back to find 120 of the leading male elders, their wives and their children either dead or seriously wounded in the ruins of fifteen homesteads. It was the largest-scale attack by Mau Mau to date.

The response was not mourning but vengeance. That night, with the apparent complicity of European commanders, the Home Guard murdered some 200 suspected Mau Mau in an orgy of beatings and summary shootings, the mangled bodies left in the bush to be picked over by stray dogs for days afterward.

Eventually, more than 300 men gave confessions to the Mau Mau killings at Lari. But as Anderson documents, it’s impossible to know what sort of coercion might have extracted them. Recognizing that their statements would be suspect, police encouraged traumatized survivors to corroborate their testimony. Anderson finds that unreliable testimony provided the basis for eighteen hangings. Still, in the end, after appeals through the British legal system, acquittals in the Lari cases outnumbered convictions, and outraged settlers pressed for and won even harsher measures and more summary justice. The story of the countermassacre and the increasing use of systematic state counterterror, meanwhile, was buried.

With outrage growing, the British stepped up their assault, now taking it to the urban centers. During two weeks in Nairobi in 1954, the government imprisoned more than 20,000 suspected Mau Mau and sent them to screening camps, deporting another 30,000 to Kikuyu reserves. By the end of Operation Anvil, as it was known, nearly half of all Kikuyu in the city had been imprisoned without trial.

But it is the conditions of that imprisonment that reveal the depths to which the British sank to maintain the illusion of their great empire, and which would ultimately prove its undoing. Elkins has bravely done justice to that history. Her book provides a painstaking and painfully detailed look at the British detention system in Kenya, a pipeline of overflowing prison camps where inmates routinely died of infectious disease, starvation and the harshness of forced labor–if they made it through the interrogations. Those “screenings” grew progressively harsher, with guards torturing inmates by using electric shock and fire, shoving broken bottles, snakes and scorpions into their private parts, and employing a range of other sexual and scatological humiliations and brutalities in a systematic effort to physically and psychologically break the Kikuyu population.

Elkins doesn’t shy away from the survivors’ stories, no matter how gruesome. One chapter opens with a man staggering to his feet with blood oozing from his mouth and nose, lifting his head from a bucket of urine, feces and sand only to see a double image of his torturer looming over him with a club, ready to strike another blow. A settler recalls taking a suspect to the Mau Mau investigation center, then sticking around to help “soften” him up: “By the time I cut his balls off he had no ears, and his eyeball, the right one, I think, was hanging out of its socket. Too bad, he died before we got much out of him.” This book is not for the faint-hearted.

By the end of 1954 more than 52,000 Kikuyu were imprisoned in the growing British gulag. But if the camps broke some into cooperating, they drove others further into the anticolonial resistance. The only way Britain could hold on to its empire was through intensifying repression and brutality. “The hypocrisies, the exploitations, the violence, and the suffering were all laid bare in the Pipeline,” writes Elkins. “It was there that Britain finally revealed the true nature of its civilizing mission.” And though the colonial authorities did their best to conceal the camps’ conditions, by the mid-1950s their harshness was well known in London. When these abuses could no longer be denied, Anderson points out, the British government attributed them to poor judgment by a few misguided low-level individuals–another familiar story.

That story unraveled in March 1959, when eleven prisoners mysteriously died while digging ditches outside the Hola prison, home to many “hard core” Mau Mau. The official explanation was that they had accidentally died from drinking contaminated water. It took three separate investigations to reveal the truth to the British public: All eleven had been clubbed to death by African guards under the supervision of European warders. Britain’s “civilizing mission” in Kenya was over.

In 1961 Jomo Kenyatta returned home to lead a bitterly divided country. Ever a moderate, he urged Kenyans to forgive and forget the past. “In Kenyatta’s Kenya,” writes Anderson, “there would be a deafening silence about Mau Mau.”

It’s impossible to read these harrowing accounts without noting some striking parallels between the British response to Mau Mau and the American response to the threat of terrorism: the torture and humiliation of prisoners at Abu Ghraib; the denial of basic rights to Al Qaeda suspects at Guantánamo Bay; the confusion of insurgency, rebellion and terrorism; and the ongoing assaults on Iraqi civilians in the name of democracy. These two substantial books not only offer an important corrective to the long-distorted story of the end of British empire in Kenya but also serve as a stark reminder of the cynical justifications that fear can foster and that history eventually lays bare.

For the sake of unity, Kenya’s leaders (which included many British loyalists) chose to bury the truth about the assault on Mau Mau, the methods used and the people ultimately responsible for the movement’s violent suppression. Given history’s tendency to repeat itself, one must question the wisdom of such a path–then, and now.