SOYSAMBU, A MASAI NAME meaning "striped stone," lies on the eastern shore of Lake Elementeita, one of the smallest of a dozen alkaline lakes that extend in a chain through Kenya's Great Rift Valley, a giant seam in the earth created by a shift of tectonic plates 20 million years ago. When I drove past the lake on a late-summer morning, thousands of flamingos were basking in the shallow water—a pink haze dusting Elementeita's silver surface. A vast sweep of savanna, speckled with yellow-barked fever trees, rose gently from the lake: the Delamere ranch. Strange volcanic forms loomed along the shoreline, including a proboscis-like outcropping known as Delamere's Nose. I turned off the highway and followed a dirt path through the bush to a metal gate and, behind it, a ramshackle guard booth. DELAMERE ESTATES, read a crude handpainted sign. NO ENTRY WITHOUT A VOUCHER. It was as far as I could go.

Until about a hundred years ago, the land I was driving through belonged to the Masai, nomadic herders whose territory extended from northeast Kenya across the Rift Valley to the Tanzania border, in the country's southwest corner. At the turn of the last century, however, Hugh Cholmondeley, the third Lord Delamere, cast his eye on the rich grazing land on the shore of the lake. Largely to accommodate Cholmondeley and a handful of other white settlers, the British colonial government in 1904 forced Masai elders to put their thumbprints on a treaty that stripped the tribe of their ownership of the Rift Valley. The nomads were left with a divided territory, one zone south of Nairobi and the other in the highlands of Laikipia, northwest of Mount Kenya, which was taken away in 1911. In 1906, Cholmondeley purchased much of the confiscated Masai land around Lake Elementeita for little more than administrative and land-surveying costs. Even now, the property is contested. Michael Tiampati, of the Maa Civil Society Forum, a Masai activist group, insists that "the process in which the land was acquired by Delamere was fraudulent, and they are illegally there."

Hugh Cholmondeley, Thomas's great-grandfather, was known as a practical joker who liked to ride his horse into the lobby of the Norfolk Hotel in Nairobi, a favorite watering hole for white Kenyan ranchers, and shoot out the lightbulbs in the bar. But he was also a serious rancher, committed to "the political and agricultural future of British East Africa," as Beryl Markham wrote in West with the Night. He built Soysambu into one of the most successful cattle ranches in the region. His son, Thomas, spent most of his adult life in advertising in London, but his grandson, Hugh (the accused Cholmondeley's father), continues the ranching tradition. The fifth Lord Delamere, now in his seventies, has amassed 10,000 head of cattle and set up a countrywide distribution system; Delamere dairy products and beef are sold all across Kenya. Soysambu also sustains a thriving wild-animal population—about 10,000 warthogs, impalas, buffalo, zebras, giraffes, cheetahs, and lions—and for several years the family owned a safari lodge on the shores of Lake Elementeita, called Delamere Camp, which was managed by a Kenyan hotel company.

It was here, in the wealthy enclave dubbed Happy Valley, cocooned in a world of black servants, shooting lessons, and ambles through the game-rich savanna, that Thomas Patrick Gilbert Cholmondeley came of age. Hugh Simpson, a neighbor, remembers him as "a nice boy, with a formal English upbringing, always polite, an open chap." As a young teenager, Cholmondeley was sent by his parents—his mother, Lady Ann Delamere, is the daughter of one of Kenya's last colonial governors—to Eton, the elite public school in southern England, and then the Royal Agriculture College, in Gloucestershire. Back in Kenya, Cholmondeley established himself as a flamboyant presence on the white Kenyan social circuit that revolves around Rift Valley ranches and the leafy Nairobi suburb of Karen, named for one of its first denizens, Karen Blixen, author of Out of Africa. Six foot four, blandly handsome, with a fringe of blond hair framing a balding pate, Cholmondeley attracted a wide circle of people like himself: wealthy white Kenyans and British expatriates who were drawn to the romance of East Africa. A friend recalls him showing up at a Nairobi wedding wearing a purple velvet suit, towering above the crowd, holding court about a walking safari he'd just taken with friends in the bush. With a large amount of cash, a fondness for women, and a taste for adventure, he struck some people as a dilettante, an overgrown teenager with a short attention span.

"He's fun to have a drink with, but he's not a serious person," one acquaintance told me. "He'd say, 'I'm going to buy a plane and fly around Africa,' and he'd go out and get himself a single-engine Piper."

As was the case with his great-grandfather, who was once severely mauled by a lion while hunting in the East African bush, Cholmondeley's enthusiasms could get him into trouble. 1n 1991, according to London's Evening Standard, during a charity motor rally, Cholmondeley's car caught fire 50 miles from Monte Carlo, destroying part of the road and an adjacent farm, but he emerged from the accident without serious injury. Six years later, while he was hiking in the Masai Mara, a buffalo charged from the bush and attacked him. "The horn went into the back of his thigh and ripped through the back of his knee and came out his ankle," Simon Cox, a longtime friend, told me. "But it didn't wreck any arteries; he just lost a lot of flesh." Cholmondeley's injury did bring him one life-changing benefit: Cox introduced him in the hospital to Sally Brewerton, a British physician then working for Doctors Without Borders in Sudan. The couple, who married in 1998 but separated shortly before the ole Sisina killing, have two young sons, Hugh and Henry.

Cholmondeley works under his father and Chirchir as the ranch's financial manager. His parents also live at Soysambu, in a four-bedroom house about a 15-minute drive from his. By all accounts, Cholmondeley seems to share his father and great-grandfather's passion for the land and is fiercely protective of the property. Lord Delamere granted the producers of the 2001 film Lara Croft: Tomb Raider permission to shoot a scene at Lake Elementeita, but, at Cholmondeley's insistence, strict rules were set about the use of vehicles along the fragile shoreline, and he monitored the filming every step of the way.

Cholmondeley's protectiveness of the ranch also led him into an ongoing conflict with the Kenya Wildlife Service. In November 2003, the KWS banned the practice of animal culling on the country's private ranches, claiming that the existing program—in which ranchers were permitted to shoot a small amount of their wildlife each year, to prevent overgrazing and other environmental damage—was poorly controlled and that many ranchers were cheating. Connie Maina, the KWS spokesperson, told me, "The system was being abused, and the numbers of zebra, gazelles, and buffalo were dropping fast." Cholmondeley allegedly ignored the KWS prohibitions, claiming they were hurting the ranch's cattle. Nick Maes even joined Cholmondeley on a hunt at Soysambu, and his Sunday Times article describes the rancher bringing down a gazelle with a single shot. Cholmondeley had been appointed an honorary game warden by the KWS in the nineties, and he and fellow ranchers claimed that he had the right to shoot wild animals that he deemed a threat to his property, his cattle, or his staff.

"All the wildlife in the country belongs to the government, and KWS is the custodian," Maina said. "You have to go with what is the law, but Tom Cholmondeley made his own rules."