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Thomas William Sweeny

1820 – 1892

United States Army general

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About Thomas William Sweeny

Lived 1820 – 1892 (aged 71). Thomas William Sweeny was an Irish military officer and soldier.

Thomas William Sweeny (December 25, 1820 – April 10, 1892) was an Irish-American soldier who served in the Mexican–American War, the Yuma War, and as a general in the Union Army during the American Civil War.

Birth and early years Sweeny was born in Cork, Ireland, on Christmas Day, 1820. He immigrated to the United States in 1833. In 1846, he enlisted as a second lieutenant in the 2nd New York Volunteers, and fought under General Winfield Scott in Mexico. Sweeny was wounded in the groin at the Battle of Cerro Gordo, and his right arm was so badly injured at the Battle of Churubusco that it had to be amputated. For his heroics, his fellow servicemen nicknamed him "Fighting Tom". Despite this usually career-ending injury, he continued serving with the 2nd US Infantry until the outbreak of the Civil War. Sweeny was active in the Yuma War (1850–1853), fighting in several engagements against native Americans.

Civil War At the outbreak of the Civil War, Sweeny was in command of the arsenal at St. Louis, Missouri. In reply to efforts of Confederate sympathizers to induce him to surrender that important post, he declared that before he would do so, he would blow it up. As second in command, he participated in the capture of Camp Jackson in May 1861 and later assisted in organizing the Home Guard. He was chosen as the brigadier general of that organization.

Sweeny commanded the 52nd Illinois Infantry Regiment at Fort Donelson. At Shiloh, in command of a brigade, he successfully defended a gap in the Union line. He was wounded in the battle, being shot twice in his only remaining arm and once in one of his legs. Sweeny kept the field until the close of the fight, exciting the admiration of the whole army. He returned to command his regiment but returned to brigade command when General Pleasant A. Hackleman was killed at Corinth. He commanded the Second Division of the Sixteenth Army Corps in the Atlanta campaign. At the Battle of Atlanta Sweeny's division intercepted John B. Hood's flank attack. Sweeny got into a fistfight with his corps commander, General Grenville M. Dodge, when Dodge broke protocol and personally directed one of Sweeny's brigades during the fight. Sweeny received a court-martial for these actions but was acquitted. He mustered out of the volunteers in August 1865, and was dismissed for going AWOL by the end of the year.

Fenian raids In 1866, he commanded the ill-fated Fenian invasion of Canada, after which he was arrested for breaking neutrality laws between the United States and Britain, but was soon released. He was reinstated with his former rank of major later that year, and retired from the regular army in May 1870 as a brigadier general.

Death Sweeny retired to Astoria on Long Island. He died there on April 10, 1892, and is buried in Green-Wood Cemetery in Brooklyn.

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Important facts

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Also known as
General Sweeny, Thomas W. Sweeny, Thomas W. Sweeney, Thos. W. Sweeny, T. W. Sweeny

People in Thomas William Sweeny's life

Named in this biography and alive at the same time

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People whose lives overlapped Thomas William Sweeny's

Frequently asked questions

Who was Thomas William Sweeny?

United States Army general (1820–1892)

When was Thomas William Sweeny born?

Thomas William Sweeny was born on 25 December 1820 in Cork.

When did Thomas William Sweeny die?

Thomas William Sweeny died on 10 April 1892 in Long Island.

What was Thomas William Sweeny's occupation?

Thomas William Sweeny was a military officer and soldier.

What nationality was Thomas William Sweeny?

Thomas William Sweeny was Irish.

Sources & further reading

· Wikipedia: Thomas William Sweeny

· Wikidata: Q7795168

· DBpedia: Thomas William Sweeny

Cite this page

APA: Biography.guide. (2026). Thomas William Sweeny. https://biography.guide/thomas-william-sweeny/

MLA: "Thomas William Sweeny." Biography.guide, https://biography.guide/thomas-william-sweeny/.

Chicago: "Thomas William Sweeny." Biography.guide. https://biography.guide/thomas-william-sweeny/.

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