An illustrtaion of the stranded Donner Party in the Sierra Nevada Mountains. (ASSOCIATED PRESS)

Timothy R. Smith is a former staff member of Book World.

Sarah Murphy Foster sat by a campfire in the early winter of 1847, grieving the death of her brother, Lemuel.

“She looked up,” the historian Michael Wallis writes, “and noticed some of the emigrants on the other side of the fire roasting meat spitted on sticks. Suddenly, Sarah realized she was watching someone eat the broiled heart of her cherished younger brother.”

Her husband guided the distraught woman away.

“The Best Land Under Heaven,” by Michael Wallis (LIVERIGHT)

Foster was a member of the Donner Party, a band of American pioneers who had set out for California in the spring of 1846. After a series of mishaps, the party became snowbound in the Sierra Nevada mountains. Lemuel Murphy died of starvation, one of 35 to perish that winter.

Their story is told by Michael Wallis in “The Best Land Under Heaven,” an even-handed, briskly written history of the party, destined to become the standard account of this horrid chapter of American history.

Much of the Donner Party’s journey was typical of the voyage west. The pioneers traded with Indians, visited fur-trading posts, hunted buffalo. There were births and marriages, deaths and burials. A cattle driver amputated a boy’s leg with “a common butcher-knife, a carpenter’s handsaw, and a shoemaker’s awl to take up the arteries.”

The operation lasted 105 minutes, and the boy died. Wagon accidents, Wallis reports, were the most frequent cause of injury and death on the pioneer trails.

That was hardly the worst of it for the Donner Party.

The group, much delayed by a tendency to dawdle, made a crucial error when it diverged from the well-established California Trail above the Great Salt Lake for a shortcut through the desert salt flats below the lake. That route was offered by Lansford Hastings in an 1845 guidebook for Oregon and California pioneers. It proved to be the party’s undoing.

“The toll of the desert crossing was the loss of three dozen animals, four wagons, many of the emigrants’ belongings and, most important, eleven precious days,” Wallis writes.

The party entered the Sierra Nevada in late fall, the worst timing possible. Hastings explained why: “Unless you pass over the mountains early in the fall,” he wrote, “you are very liable to be detained, by impassable mountains of snow, until the next spring, or, perhaps, forever.”

The group was walloped by snow, one of 10 monstrous, unforgiving storms to pound the Sierras that winter.

Stranded in the mountains, the party subsisted on field mice and twigs and a broth of boiled cattle and bison hides. The meager supplies did little to stave hunger.

“They grew weaker and frequently felt dizzy as their fat reserves and muscles were depleted,” Wallis writes. “The simplest tasks became difficult. Diminished circulation caused feet, ankles, and hands to swell. With continued weight loss, the emigrants experienced painful constipation followed by uncontrollable diarrhea. Their immune systems broke down, which made them susceptible to various infections.”

Some members of the party resorted to cannibalism.

It took four relief parties until the spring of 1847 to rescue the 46 survivors.

The Donner Party’s fate, Wallis writes, “resulted from poor decisions, inadequate preparation, quirks of fate, squadered opportunities, and failure to learn from mistakes.”

One survivor later offered a hard-earned lesson: “Remember, never take no cutoffs and hurry along as fast as you can.”

The Best Land Under Heaven
The Donner Party in the Age of Manifest Destiny

By Michael Wallis

Liveright.

453 pp. $27.95