Nathaniel Lyon

1818–1861

Nathaniel Lyon was a Brigadier General in the Union Army during the early days of the Civil War. Lyon is most well-known for leading Union forces in Missouri in the early part of the war and for being the first General from the Union Army killed in action.

Nathaniel Lyon was killed during the Battle of Wilson’s Creek, on August 9, 1861, making him the first Union general to die in combat during the Civil War. Image Source: National Park Service.

Overview

Nathaniel Lyon (1818–1861) was a career military officer from Connecticut and the first Union General to die in the Civil War. He graduated from West Point (1841) and served in the Seminole War and Mexican-American War. Lyon played a significant role in the battle for control of Missouri in the early part of the Civil War, including the Camp Jackson Affair and the Battle of Boonville. Unfortunately, Lyon was killed at the Battle of Wilson’s Creek on August 9, 1861.

Personal Facts

  • Full Name: Nathaniel Lyon
  • Birth Date: July 14, 1818
  • Birthplace: Ashford, Connecticut
  • Parents: Amasa Lyon and Kezia (Knowlton) Lyon
  • Education: United States Military Academy (1841)
  • Occupation: Military officer
  • Positions: Captain (USA), Brigadier General (USVA)
  • Spouse: None
  • Died: August 9, 1861, Springfield, Missouri.
  • Buried: Phoenixville Cemetery, Eastford, Windham County, Connecticut

Biography

Early Life

Nathaniel Lyon was born on July 14, 1818, in Ashford, Connecticut. He was the seventh of nine children of Amasa Lyon and Kezia Knowlton Lyon. Lyon’s father was a farmer and local justice of the peace. During his youth, Lyon worked on the family farm and attended public schools. In 1837, Lyon received an appointment to the United States Military Academy. He graduated eleventh in his class of fifty-two cadets on July 1, 1841.

U.S. Army Officer

After graduating from West Point, Lyon served in the 2nd U.S. Infantry in Florida, where he took part in the Seminole Wars. In 1842, he transferred to garrison duty in Sackets Harbor, New York. While there, officials court-martialed him and placed him on suspension for five months for severely beating an enlisted man.

Mexican-American War

Like many of his fellow West Point graduates, Lyon took part in the Mexican-American War (1846-1848). During that conflict, Lyon attained the rank of first lieutenant on February 16, 1847. Later that year, on August 20, he became a brevet captain, “for gallant and meritorious conduct in the battles of Contreras and Churubusco.”

Indian Massacres

After the Mexican-American War, Lyon briefly served at Ft. Hamilton, New York, in 1848. The next year, he transferred to California, where he served in various posts until 1853. While in California, Lyon led an expedition against the Pomo Indians in 1850 in retaliation for the killing of two white men. During the campaign, in an event known as the Bloody Island Massacre, Lyon directed the execution of between 60 and 400 innocent Indians whom he misidentified as the group he was pursuing. Later during the operation, his soldiers killed seventy-five more Indians along the Russian River. One year later, Lyon attained the rank of captain.

Bleeding Kansas

In 1854, Lyon transferred to Jefferson Barracks, Missouri, and then to Fort Riley in Kansas, during the Border War between Kansas and Missouri, known as Bleeding Kansas. While stationed in Kansas, Lyon witnessed the atrocities perpetrated by Missouri Border Ruffians and Kansas Jayhawkers. Lyon sided with the Free Soilers. Although he was not an abolitionist, Lyon developed a deep dislike for Missouri slaveholders and their supporters.

Civil War

As the Union unraveled after the election of President Abraham Lincoln, Lyon deployed, along with two companies of infantrymen, to guard the federal arsenal at St. Louis, in January 1861. While stationed there, Lyon developed a friendship with Congressman Frank Blair, a prominent Radical Republican. Lyon used his influence with Blair to manipulate his appointment as commander of the St. Louis arsenal.

After the fall of Fort Sumter, Lyon suspected that Missouri secessionists, led by Governor Claiborne Jackson and the state militia, were plotting to seize the St. Louis arsenal. On May 10, 1861, Lyon ordered his troops to surround and imprison approximately 670 members of the Missouri Volunteer Militia who were training at Camp Jackson, near St. Louis.

Lyon then marched his prisoners through the streets of St. Louis, inciting pro-secessionist residents to protest. When a riot ensued, Lyon’s soldiers fired on the angry crowd, killing twenty-eight civilians and wounding up to fifty more. Lyon’s actions fanned anti-Union flames in Missouri. On May 11, the Missouri General Assembly approved a measure that created the Missouri State Guard, commanded by former Governor Sterling Price. The state legislature also granted Governor Jackson with extensive executive powers to resist Union forces in the state.

Union Army Officer

Following the Camp Jackson Affair, Price met with Lyon’s superior officer, Brigadier General William S. Harney, commander of the Department of the West. To maintain peace in Missouri, the two men concluded a pact known as the Price-Harney Agreement on May 21, 1861. The agreement charged the Missouri State Guard with the responsibility of protecting pro-Unionist citizens in Missouri. When Price could not fulfill his end of the bargain, Blair contrived to have Lyon replace Harney. Officials promoted Lyon to the rank of brigadier general effective May 17, 1861, and assigned him to replace Harney as commander of the Department of the West on May 30.

On June 11, 1861, Governor Jackson met Lyon at the Planter’s House Hotel in St. Louis, in an eleventh-hour attempt to avert war in Missouri. After four hours of wrangling proved fruitless, Lyon, who was combative by nature, abruptly stormed out of the meeting declaring, “This means war!”

Governor Jackson returned to the Missouri capital at Jefferson City and evacuated the state government to Boonville on June 13, 1861. Two days later, Lyon landed an invasion force by steamboat and occupied Jefferson City unopposed. Lyon then pursued Jackson and routed Price and the Missouri State Guard at the Battle of Boonville on June 17. Jackson and the pro-secessionist members of the general assembly fled to the southwest corner of the state, leaving most of Missouri under federal control.

Throughout the summer, Price’s State Guard received reinforcements from other southern states. The Confederates united and reorganized their troops to form the Army of the West, commanded by Brigadier General Ben McCulloch.

Death at the Battle of Wilson’s Creek

As McCulloch’s army continued to grow, Lyon determined to go on the offensive. On August 9, 1861, he led nearly 5,400 Union soldiers out of Springfield, Missouri to assault over 11,000 Rebels encamped near Wilson’s Creek, roughly twelve miles southwest of the city. Lyon’s surprise attack, on the morning of August 10, caught the Confederates off guard. The Federals initially drove the Rebels back, but the Southerners eventually halted the Union advance. The Confederates launched three counterattacks during the day, but despite being outnumbered over two to one, the Yankees held their ground. During the battle, Rebel soldiers killed Lyon, making him the first Union general to die in combat during the Civil War. Major Samuel D. Sturgis took command of the Union army and, as his exhausted soldiers ran low on ammunition, he ordered a retreat later in the day. The spent Rebels did not pursue.

During the confusion caused by the retreat, Lyon’s body remained on the battlefield where Rebel soldiers recovered it. The Confederates buried Lyon’s remains on a Union soldier’s farm near Springfield. Lyon’s relatives later claimed the body for re-burial in the family plot at Phoenixville Cemetery, in Windham County, Connecticut. The general’s funeral train stopped for observances in Cincinnati, Philadelphia, New York, and Hartford during the trip back to his hometown. Lyon’s body was interred in its final resting place on September 5, 1861.

Accomplishments and Milestones

  • 1818, July 14 — Nathaniel Lyon was born in Ashford, Connecticut, the seventh of nine children to Amasa and Kezia (Knowlton) Lyon.
  • 1837 — He entered the United States Military Academy at West Point.
  • 1841, July 1 — Lyon graduated 11th out of 52 cadets from West Point and was assigned to the 2nd U.S. Infantry, serving in the Seminole Wars in Florida.
  • 1842 — He was court-martialed and suspended for five months after assaulting an enlisted man while stationed in Sackets Harbor, New York.
  • 1847, February 16 — Lyon earned a promotion to first lieutenant during the Mexican-American War.
  • 1847, August 20 — He was brevetted to captain for gallantry at the battles of Contreras and Churubusco.
  • 1850 — Lyon led an expedition in California, resulting in the Bloody Island Massacre, where federal troops killed between 60 and 400 Pomo Indians.
  • 1851 — He received a promotion to captain.
  • 1854 — Lyon was transferred to Fort Riley, Kansas, where he grew increasingly opposed to Missouri slaveholders after witnessing violence during the Kansas-Missouri Border War.
  • 1860 — While stationed in St. Louis, he developed a friendship with Radical Republican Congressman Frank Blair.
  • 1861, May 10 — Lyon orchestrated the Camp Jackson Affair, imprisoning 670 Missouri Volunteer Militia members near St. Louis, an event resulting in the deaths of 28 civilians.
  • 1861, May 17 — He was promoted to brigadier general.
  • 1861, May 30 — Lyon replaced Brigadier General William S. Harney as commander of the Department of the West.
  • 1861, June 11 — He met with Missouri Governor Claiborne Jackson, ending the meeting with the declaration, “This means war.”
  • 1861, June 15 — Lyon occupied Jefferson City, Missouri, without resistance.
  • 1861, June 17 — He defeated Major General Sterling Price’s Missouri State Guard at the Battle of Boonville.
  • 1861, August 9 — Lyon led 5,400 Union troops against over 11,000 Confederates at the Battle of Wilson’s Creek. He was killed during the battle, becoming the first Union general to die in the Civil War.

Citation Information

The following information is provided for citations, including APA Style, Chicago Style, and MLA Style.

  • Article Title Nathaniel Lyon
  • Date 1818–1861
  • Author
  • Keywords Nathaniel Lyon
  • Website Name American History Central: The Encyclopedia of American History
  • Publisher American History Central
  • Producer R.Squared Communications, LLC
  • Date Published
  • Last Update January 28, 2025
  • Access Date October 10, 2026

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