Jean-Robert Argand introduced the term " module " ' unit of measure ' in French in 1806 specifically for the complex absolute value and it was borrowed into English in 1866 as the Latin equivalent " modulus ".

* 1866 – Wassily Kandinsky, Russian-born French abstract painter ( d. 1944 )

* 1944 – Romain Rolland, French writer, Nobel laureate ( b. 1866 )

* 1944 – Wassily Kandinsky, Russian-born French artist ( b. 1866 )

Éric Alfred Leslie Satie () ( 17 May 1866 – Paris, 1 July 1925 ; signed his name Erik Satie after 1884 ) was a French composer and pianist.

Three wars led to military successes and helped to convince German people to do this: the Second war of Schleswig against Denmark in 1864, the Austro-Prussian War against Austria in 1866, and the Franco-Prussian War against the Second French Empire in 1870 – 71.

* 1804 – Paul Gavarni, French caricaturist ( d. 1866 )

These reforms included guarantees to ensure the Ottoman subjects perfect security for their lives, honour, and property ; the introduction of the first Ottoman paper banknotes ( 1840 ) and opening of the first post offices ( 1840 ); the reorganization of the finance system according to the French model ( 1840 ); the reorganization of the Civil and Criminal Code according to the French model ( 1840 ); the establishment of the Meclis-i Maarif-i Umumiye ( 1841 ) which was the prototype of the First Ottoman Parliament ( 1876 ); the reorganization of the army and a regular method of recruiting, levying the army, and fixing the duration of military service ( 1843 – 44 ); the adoption of an Ottoman national anthem and Ottoman national flag ( 1844 ); the first nationwide Ottoman census in 1844 ( only male citizens were counted ); the first national identity cards ( officially named the Mecidiye identity papers, or informally kafa kağıdı ( head paper ) documents, 1844 ); the institution of a Council of Public Instruction ( 1845 ) and the Ministry of Education ( Mekatib-i Umumiye Nezareti, 1847, which later became the Maarif Nezareti, 1857 ); the abolition of slavery and slave trade ( 1847 ); the establishment of the first modern universities ( darülfünun, 1848 ), academies ( 1848 ) and teacher schools ( darülmuallimin, 1848 ); establishment of the Ministry of Healthcare ( Tıbbiye Nezareti, 1850 ); the Commerce and Trade Code ( 1850 ); establishment of the Academy of Sciences ( Encümen-i Daniş, 1851 ); establishment of the Şirket-i Hayriye which operated the first steam-powered commuter ferries ( 1851 ); the first European style courts ( Meclis-i Ahkam-ı Adliye, 1853 ) and supreme judiciary council ( Meclis-i Ali-yi Tanzimat, 1853 ); establishment of the modern Municipality of Istanbul ( Şehremaneti, 1854 ) and the City Planning Council ( İntizam-ı Şehir Komisyonu, 1855 ); the abolition of the capitation ( Jizya ) tax on non-Muslims, with a regular method of establishing and collecting taxes ( 1856 ); non-Muslims were allowed to become soldiers ( 1856 ); various provisions for the better administration of the public service and advancement of commerce ; the establishment of the first telegraph networks ( 1847 – 1855 ) and railroads ( 1856 ); the replacement of guilds with factories ; the establishment of the Ottoman Central Bank ( originally established as the Bank-ı Osmanî in 1856, and later reorganized as the Bank-ı Osmanî-i Şahane in 1863 ) and the Ottoman Stock Exchange ( Dersaadet Tahvilat Borsası, established in 1866 ); the Land Code ( Arazi Kanunnamesi, 1857 ); permission for private sector publishers and printing firms with the Serbesti-i Kürşad Nizamnamesi ( 1857 ); establishment of the School of Economical and Political Sciences ( Mekteb-i Mülkiye, 1859 ); the Press and Journalism Regulation Code ( Matbuat Nizamnamesi, 1864 ); among others.

* 1947 – Gilbert Bougnol, French fencer ( b. 1866 )

Among its accomplishments, the United Province of Canada negotiated the Reciprocity Treaty of 1854 with the United States, built the Grand Trunk Railway, improved the educational system in Canada West under Egerton Ryerson, reinstated French as an official language of the legislature and the courts, codified the Civil Code of Lower Canada in 1866, and abolished the seigneurial system in Canada East.

* 1866 – Charles Nicolle, French bacteriologist, Nobel Prize laureate ( d. 1936 )

* 1866 – Tristan Bernard, French playwright and novelist ( d. 1947 )

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

By 1866, the French Army completely withdrew from Mexico ; Maximilian was executed by Juárez in 1867.

** La Goulue, French dancer ( b. 1866 )

* February 28 – Charles Nicolle, French bacteriologist, recipient of the Nobel Prize in Physiology or Medicine ( b. 1866 )

** Charles Mangin, French general ( b. 1866 )

* July 1 – Erik Satie, French composer ( b. 1866 )

An Italian translation of this revised French text, re-using much of the original 1866 translation by de Lauzières, was made by Angelo Zanardini.

In 1866, reacting to greater numbers of Korean converts to Catholicism despite several waves of persecutions, the Joseon court clamped down on them, massacring French Catholic missionaries and Korean converts alike.

In December 1866, the last of the French troops departed from Rome, in spite of the efforts of the pope to retain them.

* Aimé Paris ( 1798 – 1866 ), French music educator and stenographer

French interests in China were upheld in the Second Opium War and the Taiping Rebellion ; an abortive campaign against Korea was launched in 1866 while a military mission to Japan failed to prevent the restoration of Imperial rule.

The French military mission to Japan ( 1867 – 1868 ) before its departure in 1866.

Its first daily edition, that of 16 November 1866 sold 56, 000 copies.

In June 1866 the state, at private sale, sold the road to Frémont.

By 1866, he harvested 20, 000 pounds of Burley tobacco and sold it in 1867 at the St. Louis Fair for $ 58 per hundred pounds.

Reed and Wade then sold the grant to J. O. Eldredge on June 18, 1866 for $ 5, 000.

Reconstruction days began and John Pullin, Hogan's son-in-law, had the town laid out in business lots which were sold at an Administrators sale in 1866.

Broadlands was sold to John T. Alexander in 1866, and it was broken up upon his death in 1876 to pay his creditors

By 1866, following the American Civil War, the government moved the Confederated Tribe of Peoria to Oklahoma, and the land they once occupied was sold to settlers.

The original James Hamilton and Company did not last long, however, and in 1866 was sold to Leet ’ s son Frank and a son-in-law named John Jones.

A share of the business had been sold in 1866, but he continued to hold the majority interest for the next fourteen years until he sold out completely to Thomas Reppert and W. T.

Rapola was sold when his grandfather shot himself in 1866, and Svinhufvud moved to Helsinki with his mother and his sister.

*, was a screw steamer built in 1860 ; served in the American Civil War and sold in 1866

It was sold in 1866.

In 1866 the Zeiss workshop sold their thousandth microscope.

By 1866 the Zeiss workshop sold their 1, 000 microscope.

The Crown sold its last interests in the town in 1866.

The Remington derringer was sold from 1866 to 1935.

The line was sold to the Great Western Railway and its " Associated Companies " ( the Bristol and Exeter Railway and South Devon Railway ) on 1 January 1866.

In 1813, the first Kirkcaldy whaling ship, The Earl Percy, sailed north to the Davis Strait ; the town's last whaler, The Brilliant, was sold in 1866 to Peterhead, bringing an end to the industry.

* The first was an ironclad river gunboat commissioned in 1862, sunk twice in battle and raised each time, and sold in 1866.

* The third Circe was a 46-gun fifth-rate launched in 1827, confined to harbour service in 1866, renamed HMS Impregnable in 1916 and sold 1922.

His Handbook of the Stars ( 1866 ) was refused by Messrs Longmans and Messrs Macmillan, but being privately printed, it sold fairly well.

The connecting railroad was leased to the Philadelphia and Reading Railroad on July 26, 1862, and sold outright in January 1866.

Although Vernors is the oldest surviving ginger ale sold in the United States, there were a number of brands of ginger ale, ginger soda, and ginger beer sold in commerce prior to 1866.