The Mexican War and the Santa Fe Trail, 1846-1848
The Mexican War and the Santa Fe Trail, 1846-1848 witnessed a dramatic shift in its function and significance. Beginning with the outbreak of hostilities on May 13, 1846, and culminating in the Treaty of Guadalupe-Hidalgo in 1848, this conflict fundamentally altered the landscape of the American Southwest and redefined the role of this vital trade route. The United States’ acquisition of vast territories following the war, including present-day California, Nevada, Utah, and parts of several other states, brought the entirety of the Santa Fe Trail under domestic jurisdiction, transforming it from an international artery to a vital component of the burgeoning American nation. However, even under American control, the trail continued to facilitate international trade, albeit with a new dynamic.
The seeds of conflict between the United States and Mexico were sown long before the formal declaration of war. Mexico viewed Texas and the United States as separate entities. The annexation of the Republic of Texas by the U.S. Congress on March 1, 1845, acted as a major catalyst, significantly straining already fragile relations. This act was perceived by Mexico as a direct challenge to its sovereignty and a blatant disregard for its territorial integrity. The annexation of Texas, coupled with the aggressive territorial expansionism of the United States in the 1840s, created an atmosphere of increasing tension and mistrust.
The Mexican War and the Santa Fe Trail, 1846-1848 were linked by westward expansion. The westward migration of American citizens into northern Mexico via the Santa Fe Trail further exacerbated the situation. These settlers often brought with them a sense of entitlement and a disregard for Mexican laws and customs, leading to clashes and friction with the local population. A contentious boundary dispute between Texas and Mexico further fueled the fire, with both sides claiming vast swathes of territory.
U.S. citizens’ financial claims against Mexico added another layer of complexity to the deteriorating relationship. American investors and entrepreneurs had long engaged in commercial activities in Mexico, and disputes over contracts, property rights, and other financial matters were common. These claims, often exaggerated or unsubstantiated, were used by some in the United States to justify intervention in Mexican affairs. The chronic political instability within the Mexican government also contributed to the weakening of relations. Frequent changes in leadership, internal power struggles, and widespread corruption made it difficult for the United States to engage in meaningful diplomatic negotiations.
The election of James K. Polk as President of the United States in 1844, under the banner of Manifest Destiny, signaled a clear intention to expand American dominion across the continent. Polk’s vision included the acquisition of Oregon, Texas, and California, all seen as essential components of the nation’s westward expansion. This aggressive expansionist agenda, combined with the existing grievances and tensions, made a military confrontation with Mexico almost inevitable. Official hostilities commenced on May 13, 1846, when the U.S. Congress formally declared war on Mexico.
The Mexican War and the Santa Fe Trail, 1846-1848 was important for the Army of the West. The Santa Fe Trail played a crucial role in the unfolding conflict, serving as a vital artery for the movement of troops, supplies, and information. Among the first U.S. forces to utilize the trail for military purposes was the Army of the West, commanded by Colonel Stephen Watts Kearney. This expeditionary force was tasked with securing New Mexico for the United States.
The Army of the West departed Fort Leavenworth, Kansas, on June 16, 1846, and opted to follow the Mountain Route of the Santa Fe Trail. This route was chosen strategically, as it provided access to essential water resources and a pre-established base of operations at Bent’s Fort in present-day Colorado. Bent’s Fort, a prominent trading post and a symbol of American enterprise in the region, served as a vital staging area for the Army of the West’s subsequent advance into New Mexico.
From Bent’s Fort, the Army of the West marched toward Santa Fe, New Mexico, on August 2, 1846. The army encountered virtually no resistance and entered the city unopposed on August 18, 1846. Kearney, keenly aware of the potential for resentment and resistance among the local population, sought to portray his mission as one of liberation rather than conquest. To this end, circulars were disseminated to Mexican villages in advance, promising friendship, protection, and the preservation of their rights under U.S. control.
On August 19, 1846, Brigadier General Kearney formally declared the U.S. occupation of New Mexico, effectively annexing the territory to the United States. Following the annexation, Charles Bent, a prominent American trader and businessman with strong ties to the region, was appointed as the Governor of the Territory of New Mexico on August 22, 1846.
The Mexican War and the Santa Fe Trail, 1846-1848 opened routes farther west. As the territorial boundaries of the United States expanded westward, the need for additional transportation routes became increasingly pressing. To address this demand, the Mormon Battalion, a contingent of 500 young men from Nauvoo, Illinois, under the leadership of Captain Philip St. George Cooke, was dispatched from Fort Leavenworth, Kansas, to provide support for the Army of the West. Their primary mission was to construct a wagon road from the Rio Grande River to California, facilitating the movement of troops and supplies to the Pacific coast.
The Mormon Battalion followed the Cimarron Route of the Santa Fe Trail and encountered some resistance in New Mexico in 1847. Reinforcements were dispatched via the Santa Fe Trail under the command of Colonel Sterling Price, who successfully quelled the uprising and maintained U.S. control over the territory. Simultaneously, another detachment of the Army of the West, under the command of Colonel Alexander Doniphan, marched down the Rio Grande Valley to capture Chihuahua, Mexico. Chihuahua had become a popular destination for Santa Fe traders, solidifying the trail’s commercial significance.
Throughout the duration of the Mexican War, troops assigned to occupy New Mexico were routinely dispatched over the Santa Fe Trail. Notably, many individuals who gained familiarity with the trail during their military service later returned as traders, further contributing to the trail’s commercial development. Resistance to U.S. occupation persisted in the form of guerrilla warfare, with insurrections erupting in Taos and Mora, New Mexico, in early 1847. Tragically, Governor Charles Bent perished in the Taos confrontation, highlighting the volatile nature of the conflict.
The signing of the Treaty of Guadalupe-Hidalgo in 1848 marked the formal end of the war but signaled the beginning of an era of expanded trade and commerce along the Santa Fe Trail. It is estimated that during the summer of 1848 alone, approximately three thousand wagons, carrying 12,000 people and 50,000 head of livestock, traversed the trail, underscoring its growing importance as a conduit for westward expansion and economic development.
The increasing utilization of the Santa Fe Trail during the Mexican War had detrimental consequences for American Indian habitation and their way of life. Big Timbers, a region located east of Bent’s Old Fort on the Arkansas River in Colorado, serves as a stark example of this phenomenon. Between 1846 and 1847, the surge in traffic along the Santa Fe Trail led to the disruption of habitats, the depletion of game, the pollution of water sources, and the indiscriminate felling of trees.
These incursions resulted in the deaths of 47 trail travelers, the destruction of 330 wagons, and the theft of 6,500 animals. In response to these escalating threats, a battalion of troops was assigned to guard wagon trains in September 1847. Initially, roving columns of soldiers were employed, but this mobile police force proved ineffective due to the vast length of the corridor that needed to be patrolled.
With the signing of the Treaty of Guadalupe-Hidalgo, the United States acquired a vast expanse of territory, encompassing present-day New Mexico, Arizona, California, Nevada, and Utah, as well as portions of Colorado, Wyoming, Oklahoma, Kansas, and Texas. The Texas Annexation of 1845 and the Mexican Cession of 1848 paved the way for the creation of California, the Utah Territory, the New Mexico Territory, and the state of Texas, with the remaining land constituting unorganized territory.
Despite the United States’ preparations for war with Mexico, certain aspects of the military operation, particularly as they related to the Santa Fe Trail, appear to have been inadequately considered. The method of supplying the army, for instance, revealed a lack of foresight, as provisions often arrived at military outposts faster than wagons could be procured for their distribution. Furthermore, the drivers of these wagons were frequently inexperienced, further complicating logistical challenges.
The Mexican War and the Santa Fe Trail, 1846-1848 altered the trade. The Mexican War fundamentally altered the pattern of the Old Santa Fe trade. While New Mexican and interior Mexican merchants continued to participate in the trade, their share of the market declined following the war. The Santa Fe Trail transitioned from foreign to domestic jurisdiction, and small proprietors were increasingly displaced by large freighting companies. As the commercial value of merchandise increased, the Santa Fe trade expanded, becoming an integral part of the American economy.