* 1866 – José de Diego, Puerto Rican statesman and journalist ( d. 1918 )

Tristan Bernard ( 7 September 1866 – 7 December 1947 ) was a French playwright, novelist, journalist and lawyer.

* August 9 – Lincoln Steffens, American journalist ( b. 1866 )

* James Aldrich, ( 1810 – 1866 ), born in Mattituck, noted poet and journalist

Another nephew was Theodore Dwight ( 1796 – 1866 ), an author and journalist.

During the reign of Domnitor Alexandru Ioan Cuza ( 1859 – 1866 ), Catargiu was one of the Opposition leaders, and received much assistance from his kinsman, Barbu Catargiu ( b. 1807 ), a noted journalist and politician, who was assassinated in Bucharest on the June 20, 1862.

* April 6-Godfroy Langlois, politician, journalist and lawyer ( b. 1866 )

* January 9-John Wesley Dafoe, journalist and author ( b. 1866 )

José de Diego y Martínez ( April 16, 1866 – July 16, 1918 ), known as " The Father of the Puerto Rican Independence Movement ", was a statesman, journalist, poet, lawyer, and advocate for Puerto Rico's independence from Spain and from the United States.

* September 17-Jean-Baptiste-Éric Dorion, journalist and politician ( died 1866 )

After experience as a medical student, a clerk at the Hôtel de Ville in Paris, a playwright and a journalist, he joined the staff of Le Figaro in 1863 ; but a series of his articles, afterwards published as Les Français de la décadence ( 3 vols., 1866 – 68 ), brought the paper into collision with the authorities and caused the termination of his engagement.

* William Flavelle Monypenny ( 1866 – 1912 ), British journalist

William Flavelle Monypenny ( 7 August 1866 – 23 November 1912 ) was a British journalist and editor who was the biographer of Benjamin Disraeli.

A notorious incident in which Sheehan ’ s colleague satiric poet and journalist Francis Sylvester Mahony, Father Prout ( 1804 – 1866 ) fell out with Celbridge parish priest James Callinan took place at Sheehan ’ s home in Celbridge in 1830.

Euclides da Cunha (, January 20, 1866 – August 15, 1909 ) was a Brazilian journalist, sociologist and engineer.

Hermann Löns ( 1866 – 1914 ) was a German journalist and writer.

* Rodolphe Lemieux ( 1866 – 1937 ), Canadian journalist, lawyer, law professor, and politician

* J. E. Casely Hayford ( 1866 – 1930 ), Fante journalist, author and politician

Henry Cantwell " Harry " Wallace ( 1866 – 1924 ) was an American farmer, journalist, and political activist.

Ignacy Ewaryst Daszyński ( 26 October 1866, Zbarazh – 31 October 1936 ) was a Polish politician, journalist and Prime Minister of the Polish government created in Lublin in 1918.

George Coşbuc () ( 20 September 1866 — 9 May 1918 ) was a Romanian poet, translator, teacher, and journalist, best remembered for his verses describing, praising and eulogizing rural life, its many travails but also its occasions for joy.

Charles Maclaren ( 7 October 1782 – 10 September 1866 ) was a Scottish journalist and geologist.

Hugh Chisholm ( 22 February 1866 – 29 September 1924 ) was a British journalist, and editor of the 10th, 11th and 12th editions of the Encyclopædia Britannica.

Victor Emile Marsden ( 1866 – October 28, 1920 ) was a journalist and translator, known for allegedly translating an English language version of The Protocols of the Elders of Zion.

" The two terms, uniformitarianism and catastrophism, were both coined by William Whewell ; in 1866 R. Grove suggested the simpler term continuity for Lyell's view, but the old terms persisted.

* 1866 – Edward William Exshaw, British sailor ( d. 1927 )

As a consequence, Hanover passed to William IV's brother, Ernest Augustus, and remained a kingdom until 1866, when it was annexed by Prussia during the Austro-Prussian war.

* 1788 – William Thomas Brande, English chemist ( d. 1866 )

* 1866 – William G. Conley, American politician and 18th Governor of West Virginia ( d. 1940 )

* 1927 – Edward William Exshaw, British sailor ( b. 1866 )

* 1789 – William Burton, American politician ( d. 1866 )

In 2011, an 1866 letter written by William Herndon, Abraham Lincoln's law partner, was auctioned off for US $ 30, 000.

* December 23 – William Henry Harrison, English cricketer ( b. 1866 )

* May 24 – William Whewell, English scientist, philosopher, and historian of science ( d. 1866 )

* March 6 – William Dick, founder of Edinburgh Veterinary College ( d. 1866 )

With his brother William Conant Church he established The Army and Navy Journal in 1863, and Galaxy magazine in 1866.

In 1866, William Steinway oversaw the construction of the first Steinway Hall to the rear of the showrooms.

While recuperating in England and receiving treatment from Sir William Gull, Muybridge took up the new field of professional photography sometime between 1861 and 1866.

( Rev Dunmore Lang 1861, William Ridley 1866 ).

* Henry William Connor ( 1793 – 1866 ), born near Amelia Court House, United States Congressman from North Carolina

* William Cotton ( banker ) ( 1786 – 1866 ), Governor of the Bank of England, 1842 – 1845

* William Hall Smith ( 1866 –?

The Green Dining Room 1866 – 68 was the work of Philip Webb and William Morris, displays Elizabethan influences, the lower part of the walls are panelled in wood with a band of paintings depicting fruit and the occasional figure, with moulded plaster foliage on the main part of the wall and a plaster frieze around the decorated ceiling and stained glass windows by Edward Burne-Jones.

William R. Milligan arrived in 1866, followed by Frank Walker in 1870.

William Wetherell first came to America in 1866 to work in Philadelphia, on the preparations for the big Centennial celebration.

The village of Red Bud was organized on April 19, 1866, with officers as follows: John Brickey – president of board, Gerhard Boekhoff, William Schuck, Gerhard Ortgeisen, and John Brunner.

This was the second hotel, the first having been built in 1866 by William A. Hogaboom.

* Dover is a mostly historical settlement in the northeast part of the township at The first settlers in Clare County, the family of William Crawford, settled near Dover in 1866.

Moberly was founded in 1866, and named after Colonel William E. Moberly, the first president of the Chariton and Randolph County railroads.