As Sarah and her family navigated the Platte River in 1846, Mariano Vallejo, the influential leader of the Mexican Province of Alta California, pondered the possibility of California gaining complete independence from Mexico. In June, a band of freelance revolutionaries linked to the US army aimed to arrest Vallejo, force his capitulation, and proclaim the independent Republic of California. Vallejo, instead of making an escape, invited them in for a drink and even collaborated in drafting the document that declared California’s independence.

Meanwhile, as the Graves family proceeded along the Platte River toward Fort Laramie, they encountered increasingly dry and dusty conditions that compounded the difficulties of travel and daily life. On June 17, the Graves party made camp with other wagons. A nighttime raid by Indigenous Americans led to a substantial loss of their cattle, posing a significant threat to their expedition. To retrieve the cattle, two men set out; one of the men, Timble, was killed, leaving behind a pregnant widow. This tragedy highlighted the brutal realities of westward expansion, including the risk of women being widowed on the journey, children succumbing to accidents or illnesses, and other dangers that plagued pioneers’ daily lives.