The Walker Expedition: Unmanifested Destiny

Written by Sam Marks

From its founding in 1776, the United States of America wasted no time when it came to gaining territory. Not even one hundred years into the country’s existence, it had already acquired territory stretching from the Atlantic to the Pacific Ocean, gaining its foundational borders practically three times over. Driven by a desire to rid the American continent of European colonialism and the perceived savagery of Native Americans, the US took on the role of a protector against inter-continental threats.  

This protector belief was what journalist John L. O’Sullivan called “Manifest Destiny,” the cultural belief that the US was self-interested and morally just in its expansion across the American continent. Various political developments contributed to a strong desire for the frontier. Manifest Destiny was, in large measure, supported by Southern slave-owners of the Democratic party, at the time a pro-slavery expansionist party. The plantation gentry viewed the lands beyond the Mississippi River as prime real estate to develop new slave-based enterprises where cotton was king and costs were low. Members of the Whig party, located mostly in northern states where slavery had been outlawed, were opposed to the expansion of slavery and viewed Manifest Destiny as a leading cause of divisiveness regarding what territories would be admitted as free states or slave states. Though Democratic politicians were successful in acquiring territory from the Mexican-American War and border disputes in Oregon, internal political disputes over the presence of slavery in the newly acquired territories halted the progress of Manifest Destiny from the US government after the 1840s. But throughout the 1850s, various paramilitary attempts were made outside of US law to acquire new territory and expand slavery in a process known as “filibustering” (the 1850s definition of “filibuster” differed significantly from the modern-day definition, which describes a US Senator refusing to give up one’s speaking time on a Congressional bill to delay or prevent the voting process from occurring). The most notable filibustering was done by a man named William Walker.  

Quite the eccentric character, William Walker, born in Nashville, Tennessee in 1824, showed exceptionality from an early age. He graduated summa cum laude from the University of Nashville at age 14. By age 19, he had received a medical degree from the University of Pennsylvania and continued his studies at the Universities of Edinburgh and Heidelberg throughout his early twenties. Returning to Pennsylvania, he practiced medicine, but traded in the practice for law, which he privately studied in New Orleans. Another career change brought Walker into the publishing business, as he co-owned the New Orleans Crescent newspaper.  Jumping on the bandwagon that was the California Gold Rush, Walker moved to San Francisco in 1849, serving as an editor for the San Francisco Herald. He was a well-dressed man who, despite his small stature of five foot two, was known for his commanding presence and energetic persona. At the age of 25, Walker had acquired two degrees, had alma maters in four universities, had moved to Europe and across the United States, and had been a successful newspaperman in two major cities. But after all these accomplishments, Walker had a great thirst for making history rather than just reporting it.  

While in San Francisco, Walker had become inspired by Venezuelan-born anti-Spanish revolutionary Narciso Lopez. From 1848 to 1849, Lopez led a series of filibusters to Cuba in order to seize control of it from Spanish rule. Like Walker, Lopez was sympathetic to the expansion of slavery and received the support of numerous Southern politicians, newspapers, and businessmen to claim Cuba. Though his expeditions to Cuba resulted in defeat and Lopez’s death, his legacy of filibustering to create a slave state became the focus of Walker’s conquests.  

Initially, Walker attempted to get the Mexican government’s approval to establish an American colony in the territory of Sonora. Following Mexico’s refusal to grant Walker a colony within their own territory, Walker, as President James K. Polk had done, set out to capture territory in Mexican lands by force. With only forty-five men, Walker aimed to establish the Republic of Sonora.  

In 1853, the group succeeded in capturing La Paz, the capital of the Baja California Mexican territory and created the Republic of Lower California, with Walker serving as president. The strip of land declared independence from Mexico on 10 January 1854 and was placed under Louisiana law, allowing slavery in the region. While never capturing Sonora, Walker later declared Lower California as the Republic of Sonora. Eventually Walker and his crew were driven out of his Republic due to lack of supplies and opposing Mexican military forces, and the land was reestablished by Mexico on 8 May 1845. Returning to California, Walker was put on trial for waging an illegal war and violating the peace treaty of Guadalupe Hidalgo that ended the Mexican-American War. However, the high support for Manifest Destiny in the western United States at the time saw him acquitted in a mere eight minutes.  

Despite the short-lived nature of his Republic, Walker’s filibuster was extremely popular in San Francisco, where bonds were traded and flags were raised for the Republic of Sonora. Secret societies, such as the Knights of the Golden Circle, were formed to help support and fund slave-expansionist projects. Walker and his passion for filibustering was not stopped by his ousting from Baja; instead, he only became more prominent and support increased for the practice. 

A major political issue in 1850s American politics was creating a quicker route of travel between the East Coast and West Coast. Though a transcontinental railroad was proposed by several in Congress, the creation of a canal in Latin America caught the eye of many, including Walker. And when civil war erupted in Nicaragua in 1854, Walker heard the call to filibustering again.  

President Francisco Castellon of the Democratic Party of Nicaragua gave Walker and his men a contract that allowed them to legally come to Nicaragua and assist in ending the Legitimist Party’s uprising against the government. Walker landed and, with the support of 300 men composed of American and local forces, began his campaign to the capital city of Granada. Among the ranks was Charles Frederick Henningsen, a military aficionado who had fought in various civil wars across Europe. Along with Henningsen, Birkett D. Fry, Robert C. Taylor, and Chatham Roberdeau Wheat would all become Confederate military leaders upon the breakout of the US Civil War. 

On 3 September 1855, Walker’s forces defeated the Legitimist forces at the Battle of La Virgen and on 13 October, Walker conquered Granada. The new regime ruled through the puppet regime of Patricio Rivas, legalizing slavery and making English the official language. In 1856, US President Franklin Pierce recognized Walker’s government as the official government of Nicaragua, allowing Walker to declare himself president and opening up the possibility of annexation to the US. However, Walker’s regime was not to last as the neighboring Central American countries did not take kindly to the usurpation of the Nicaraguan government.   

President Juan Rafael Mora of Costa Rica declared war against Walker’s regime, and his forces invaded Nicaragua and beat Walker’s forces at several key battles. The governments of Honduras, El Salvador, and Guatemala signed the Treaty of Alliance in 1856, officially recognizing Patricio Rivas as the Nicaraguan President over Walker. Loyalists to Rivas signed a “providential pact” to declare war against Walker and liberate the country from the mercenaries.  The impeding coalition of forces against Walker, a series of defeats against the Nicaraguan army, cholera outbreaks, and insufficient support from American financiers led to Walker’s forces being outnumbered and outmatched.  

By December 1856, Granada was surrounded by 4,000 Central American troops, forcing Walker and his men to escape. On Walker’s orders, Henningsen burned Granada to the ground, leaving only the “Aqui Fue Granada” sign (English: “Here was Granada”) surviving among the ruins. Expelled from Granada, on 1 May 1857, Walker surrendered to US Navy Admiral Charles Henry Davis. When Walker returned to New York, his initial heroic reputation was squandered when he criticized the US Navy for his failure to maintain his regime. But it was at this point in his life when Walker’s taste for filibustering went beyond his support for Manifest Destiny. The US, now on the verge of the Civil War, was focused infinitely more on its varying internal disputes than on garnering support for territorial expansion. So, Walker instead made use of the British to wage another military insurgency.   

The British colonists on the Bay Islands off the coast of Honduras asked for Walker’s help in establishing a separate government. The islands were controlled by British Honduras, but Walker had little objection to meddling in British affairs as he had done in the US, Mexico, Nicaragua, and Costa Rica. Unfortunately for Walker, his drive for filibustering would ultimately send him into a crash he would not recover from.  

Sailing from Trujillo, Honduras, Walker was intercepted by British Royal Navy forces and placed in custody. Like the US, Britain aimed to create a trans-oceanic canal through Honduras, but unlike the US, Walker’s presence was viewed as a threat to the British economic interests. The party Walker traveled with were handed over to Honduran authorities. In the end, Walker was executed by firing squad at age 36 on 12 September 1860. He never succeeded at getting any territory annexed by the US.  

Walker’s death came just before the US entered the Civil War in 1861. Despite his vigorous campaigns in favor of slavery, the national movement to eliminate slavery would be victorious over those who supported its spread. His actions were, like many slavery supporters of his time, reflective of the desperation to not only keep the plantation economy alive, but also to spread slavery to new lands with more potential for larger economic gain. The destiny manifested by Walker and so many others who fought for the expansion of slavery would continue to decline despite all the efforts of its bold-faced protagonist.  


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Scroggs, William O. (William Oscar). 1916. Filibusters and Financiers; the Story of William Walker and His Associates. New York, The Macmillan company. 

Soodalter, Ron. 2010. “William Walker: King of the 19th Century Filibusters.” HistoryNet, March 4, 2010. 

Walker, William. 2013. War in Nicaragua. Lexington, KY: Windham Press. 

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