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Denis O'Leary

1863 – 1943

American politician

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About Denis O'Leary

Lived 1863 – 1943 (aged 80). Denis O'Leary was an American politician and lawyer.

Denis O'Leary (January 22, 1863 – September 27, 1943) was an American educator, lawyer, and politician who served as Queens County district attorney and for one year as a member of the United States House of Representatives from New York, from 1913 to 1914.

Biography Early life and education O'Leary was born on January 22, 1863, in Manhasset, Long Island, New York. He attended and later taught in the public schools. He was graduated from the law school of New York University in 1890. O`Leary was admitted to the bar the same year and commenced practice in New York City.

Political career He was assistant corporation counsel of New York City in 1905 and 1906 and commissioner of public works of Queens Borough in 1911 and 1912.

Congress O`Leary was elected as a Democrat to the Sixty-third Congress and served from March 4, 1913, until December 31, 1914, when he resigned.

District attorney He later served as district attorney of Queens County 1915-1921.

Later career and death He resumed the practice of law until 1929 when he retired. He died in Douglaston, Queens County, N.Y., September 27, 1943.

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Important facts

Birth century
Occupation
Nationality
Education
New York University School of Law
Positions held
United States representative

Contemporaries

People whose lives overlapped Denis O'Leary's

Frequently asked questions

Who was Denis O'Leary?

American politician (1863-1943)

When was Denis O'Leary born?

Denis O'Leary was born on 22 January 1863 in Manhasset.

When did Denis O'Leary die?

Denis O'Leary died on 27 September 1943.

What was Denis O'Leary's occupation?

Denis O'Leary was a politician and lawyer.

What nationality was Denis O'Leary?

Denis O'Leary was American.

Sources & further reading

· Wikipedia: Denis O'Leary

· Wikidata: Q276969

· DBpedia: Denis O'Leary

Cite this page

APA: Biography.guide. (2026). Denis O'Leary. https://biography.guide/denis-o-leary/

MLA: "Denis O'Leary." Biography.guide, https://biography.guide/denis-o-leary/.

Chicago: "Denis O'Leary." Biography.guide. https://biography.guide/denis-o-leary/.

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