This is a list of participants in the Walker affair, an occupation of Nicaragua by American mercenary William Walker and his followers and supporters. It includes those who joined him in Nicaragua and those who supported the campaign from the United States.
William Walker.
William Walker (May 8, 1824 – September 12, 1860) was an American physician, lawyer, journalist, and mercenary. After settling in California and motivated by an earlier filibustering project of Gaston de Raousset-Boulbon, Walker attempted in 1853–54 to take Baja California and Sonora, Mexico. He declared those territories to be an independent Republic of Sonora, but he was soon driven back to California by the Mexican forces. Walker then went to Nicaragua in 1855 as leader of a mercenary army employed by the Nicaraguan Democratic Party in its civil war against the Legitimists. He took control of the Nicaraguan government and in July 1856 set himself up as the country's president.
Walker's regime was recognized as the legitimate government of Nicaragua by US president Franklin Pierce and it initially enjoyed the support of some important sectors within Nicaraguan society. However, Walker antagonized the powerful Wall Street tycoon Cornelius Vanderbilt by expropriating Vanderbilt's Accessory Transit Company, which operated one of the main routes for the transport of passengers going from New York City to San Francisco. The British Empire saw Walker as a threat to its interests in the possible construction of a Nicaragua Canal. As ruler of Nicaragua, Walker re-legalized slavery, which had been abolished in 1824, albeit this measure was never enforced, and threatened the independence of neighboring Central American republics. A military coalition led by Costa Rica defeated Walker and forced him to resign the presidency of Nicaragua on May 1, 1857.
Walker then tried to re-launch his filibustering project and in 1860 he published a book, "The War in Nicaragua", which cast his efforts to conquer Central America as tied to the geographical expansion of slavery. In that way, Walker sought to gain renewed support from pro-slavery forces in the Southern United States on the eve of the American Civil War. That same year Walker returned to Central America but was arrested by the Royal Navy, who handed him over to the Honduran government which executed him.
Henry Gaither Worthington.
Henry Gaither Worthington was an attorney. He moved to Tuolumne County, California, in the early 1850s, where he studied law and began his practice. In the mid-1850s, he joined William Walker's filibustering expeditions in Mexico and Nicaragua but later opposed Walker's pro-slavery policies. He returned from Nicaragua to the U.S. only after Walker was executed in Honduras.  Worthington served as a member of the California State Assembly from 1861 to 1862, representing the 8th District, and later became Chief Clerk of the Assembly in 1863. Upon Nevada's admission to the Union, he was elected its first U.S. Representative, serving a partial term from October 31, 1864, to March 3, 1865, during which he played a pivotal role in passing the 13th Amendment to abolish slavery. He later served as U.S. Minister to Argentina and Uruguay from 1868 to 1869. Worthington passed away in Washington, D.C., on July 29, 1909, and was buried at Congressional Cemetery.
William Matthew Ormsby.
William Ormsby was born in 1814 in Pennsylvania. He moved to California to join the Gold Rush. At age 30 he married a sixteen year old named Margaret Trumbo. He then joined Walker in his invasion of Sonora, Mexico and Baja California in 1853. After the invasion of Mexico failed, Ormsby joined Walker in the invasion of Nicaragua in 1856, where he lost a leg in battle. Ormsby’s wife did not join him in Nicaragua. By 1857 Ormsby was back in the United States. He died in 1860 in a battle against Paiute Indigenous peoples in Nevada.
Chauncey Beaman.
Chauncey Beaman (sometimes spelled Beman) was one of William Walker’s “Immortals,” joining the initial filibuster expedition to Nicaragua on May 4, 1855. He served in Company A of the First Battalion of Riflers, part of Walker’s "American Phalanx." Beaman was discharged on January 18, 1856. When Walker left Nicaragua in 1857, Beaman remained in Nicaragua.
George Dionysius Tillman.
George Dionysius Tillman was a lawyer, politician, and Confederate veteran. On July 21, 1856, Tillman shot and killed J. Henry Christian, a mechanic, at the Planters’ Hotel in Edgefield, South Carolina, during a dispute over a card game. Rather than face charges, Tillman fled the state and joined William Walker’s filibuster expedition to conquer Nicaragua. Upon his return to Edgefield, Tillman surrendered, was convicted of manslaughter, and served a two-year sentence in the county jail, continuing to practice law from his cell.
Despite this early controversy, Tillman went on to have a notable political career. He served in the South Carolina House of Representatives from 1854 to 1855 and again in 1864. During the Civil War, he enlisted in South Carolina military units, serving until 1865. Post-war, Tillman participated in the 1865 state constitutional convention and served in the South Carolina Senate later that year. He was elected as a Democrat to the U.S. House of Representatives, serving from 1879 to 1881, though he briefly lost his seat to Robert Smalls after a contested election. Re-elected in 1882, he served four additional terms from 1883 to 1893, chairing the Committee on Patents during the Fifty-Second Congress.
Tillman remained active in state politics, attending the 1895 constitutional convention and running unsuccessfully for Governor in 1898. He and his brother were prominent figures in South Carolina politics.
Augustus Calhoun Allen.
Augustus Calhoun Allen was born on March 6, 1835, and died on March 15, 1914. He was a businessman and a Confederate officer during the Civil War. On the evening of December 28, 1857, Allen departed from his home in New Orleans, Louisiana, boarding the steamship "Texas" as a volunteer bound for Nicaragua. He was an officer in Walker’s army. Back in the U.S. in 1859, he married Ellen Virginia Allen. The couple had three children. During the Civil War,  he was captured by Union forces outside of Baton Rouge, Louisiana in 1864. After the war, in 1879, Allen moved to Texas, where he became the operator of a cotton press.
John P. Heiss.
John P. Heiss was born around the year 1812. He got married in 1835 in Philadelphia. In the early 1840s, he was a part of the Tennessee militia and became a journalist. Heiss worked for William Walker in Nicaragua from 1856 to 1857. He went back to the United States in 1857. In 1861 he returned back to Nicaragua where he wanted to grow cotton. Heiss passed away in 1865.  His son served in the confederate army.
Wiley Marshall.
Wiley Marshall was a twin. His twin's name was Green Marshall. Both brothers decided they were going to join William Walker in Nicaragua in the summer of 1856 but Green never made it. Wiley died in a battle in Nicaragua and Green died in California on the same day. Wiley helped command the attack on the San Jacinto ranch in September 1856. Nicaraguans defeated the filibusters in that famous battle (the Battle of San Jacinto) and today have a national holiday to celebrate their victory over Wiley and his men.
James Caleb Smith.
James Caleb Smith was born on June 24, 1824, in Virginia, to Governor William “Billy” Smith and Elizabeth Hansbrough Bell. Governor Smith would become a Confederate general during the Civil War. An attorney, James Caleb Smith moved to California in 1850, accompanying his father, and quickly established himself as a prominent figure in the state. He served as a judge on the San Francisco Supreme Court and was also elected to the California Assembly, becoming a leader within the Democratic Party in the region. Smith became widely known for challenging Senator David C. Broderick to a duel in 1852, after Broderick made disparaging remarks about his father. The duel, held near Oakland Point and witnessed by thousands, resulted in no serious injuries, though Smith’s bullet famously struck and damaged Broderick’s watch, an incident that gained much public attention. It was in California that Smith most likely met Walker and other filibusters.  In Nicaragua Smith became involved in a land company. He contracted a fever and passed away in Nicaragua on May 2, 1856, at the age of 31. He was buried in Richmond, Virginia.
Ambrose F. Rudler (Anthony Francis Rudler).
Ambrose F. Rudler, also known as Anthony Francis Rudler, was a participant in William Walker's filibustering campaigns. Rudler was among those who joined Walker in the invasion of Mexico and later the war in Nicaragua. He was born in Alsace-Lorraine. He moved to the state of Georgia in the U.S. with his family as a child.
He was a general in the confederate army in Georgia. 
Martin P. Avery.
Martin P. Avery was born in New York in 1836. Avery was the adjutant of President Haye’s regiment. He was a member of the Masonic lodge in Kansas. Prior to his death, Martin spent time in Nicaragua as a filibuster. His time there was somewhat brief due to his untimely death.
Daniel K. Bailey.
Daniel K. Bailey was born on January 27, 1838, in Groveland, Livingston County, New York. He was elected by his fellow filibusters to serve as a lieutenant of the first battalion in Walker’s army. On February 23, 1862, Bailey married Phoebe A. Lowden. The couple had two daughters, Libbie Wood and Grace Bailey. Bailey died on April 27, 1900 and was buried in New York.
Edgar Vanover.
Edgar Vanover fought with William Walker in Nicaragua. When Walker surrendered to the Costa Rican forces in 1857 Vanover came back to the U.S. with approximately 400 other filibusters.  He then moved to California, eventually settling in Golden, Colorado. He was unable to return to Missouri because he was wanted for a crime there. In September 1859, after a day of heavy drinking and making threats against the co-owners of his saloon, Vanover was hanged to death. He was hanged for a crime he had threatened to commit.
Frank Turk.
Frank Turk, an attorney, was active in California politics. He served as president of the San Francisco Common Council. He embarked on the Sierra Nevada ship on October 20, 1855, to Nicaragua. The ship reached San Juan del Sur on November 1. Shortly after, he returned to California, departing again on December 5 on the same vessel. He arrived in Nicaragua on November 17.
Frank William Stewart.
Frank William Stewart joined William Walker's army in February 1857. On March 7, he arrived in Nicaragua as part of the last company to come from California. Stewart was appointed captain of the Red Star Guard and became known as Captain Stewart. Even though he was a captain, Stewart later spoke out against the campaign, trying to share what he believed really happened in Nicaragua and clear up false ideas people had in the U.S.  Stewart recorded detailed recollections of the battle scenes and his personal interactions with William Walker, providing valuable insight into the campaign.
James Carson Jamison.
James Carson Jamison was a soldier who served under William Walker, participating in his military campaigns in Nicaragua. He was born on September 30, 1830, in a pioneer home that was located about two and a half miles southeast of Paynesville in Pike County, Missouri. His father, John Carson Jamison, had migrated to Missouri from North Carolina during the early days of EuroAmerican settlement. In James' early years he worked as a miner in Georgetown, El Dorado County, in California, while waiting to join William Walker in Nicaragua. He received forty-four votes for the position of first lieutenant in Nicaragua from the others who were with him on the Sierra Nevada ship on their way to filibuster. He was later appointed by Walker to the company D of the first infantry.  Once he was back from Nicaragua he fought on the side of the Confederacy during the Civil War. He passed away on November 19, 1916, in Guthrie, Oklahoma, and was laid to rest in Clarksville.
Edward John Cage Kewen.
Edward John Cage Kewen, (Edward J.C. Kewen) born in 1825, was from Columbus, Mississippi. In 1855, Kewen, a close friend of Walker, joined the enterprise, taking on fiscal responsibilities in the Walker administration, traveling to the southern states to recruit men and funds for the Nicaraguan "adventure." Kewen's brother also joined Walker in Nicaragua and died there in 1855. Kewen later became a prominent criminal defense attorney and the proprietor of El Molino Viejo, an estate surrounding