HISTORY & TIMELINE

17 May

A journey through
17 May in history

The story of 17 May runs from the choice of a new bishop of Rome in 352 to rebel troops entering Kinshasa in 1997. In between come the founding of Montreal, a new constitution for Norway, the birth of the world’s first international organisation, the lifting of the siege of Mafeking, a short-lived Israel-Lebanon agreement and a violent crackdown on protesters in Bangkok.

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EARLIEST RECORDS

Ancient & Early History

The earliest worthwhile records and events connected with this date.

352

Murillo’s painting of the Roman patrician John telling Pope Liberius of his dream, from the legend of Santa Maria MaggioreImage: Bartolomé Esteban Perez Murillo · Public domain

culture · Europe

Liberius becomes bishop of Rome

After the death of Pope Julius I in April 352, the church in Rome chose the deacon Liberius as his successor; the Catholic Encyclopedia dates his election to 17 May. His long reign came at the height of the dispute over Arianism, and in 355 the emperor Constantius II sent him into exile for refusing to condemn Athanasius. He later returned to Rome and served until his death in 366.

Source: Catholic Encyclopedia (New Advent): Pope Liberius ↗

III

A CHANGING WORLD

Early Modern Era

Exploration, political change, scientific development and expanding global connections.

1642

The monument to Paul de Chomedey de Maisonneuve on Place d’Armes in MontrealImage: Frankyb602 · CC BY-SA 3.0

world · Americas

French settlers found the outpost that grew into Montreal

On 17 May 1642 a small party of French colonists stepped ashore on the island of Montreal, far up the St Lawrence River. Led by the soldier Paul de Chomedey de Maisonneuve and the nurse Jeanne Mance, and sent by a devout Paris society, they had wintered near Quebec before pushing on. A priest said Mass to mark the founding of their settlement, which they named Ville-Marie. The aim was religious: to bring Christianity to the Indigenous peoples of the region. Life in the fortified outpost was hard and often dangerous, but it survived. Mance opened a hospital, Maisonneuve served as the first governor, and the little mission gradually grew into Montreal, today one of the largest French-speaking cities in the world.

Source: The Canadian Encyclopedia: Ville-Marie (Colony) ↗

THE NINETEENTH CENTURY

The 1800s

Industry, empire, invention, reform and a century of enormous transformation.

1814

Oscar Wergeland’s 1885 painting of the Constituent Assembly at Eidsvoll in 1814Image: Oscar Wergeland · Public domain

politics · Europe

Norway adopts its constitution at Eidsvoll

Early in 1814 the Treaty of Kiel handed Norway from Denmark to Sweden, and many Norwegians refused to accept it. Elected representatives gathered at a manor house at Eidsvoll, north of Christiania (now Oslo), and after weeks of debate they laid down a constitution on 17 May 1814. The same day they chose the Danish prince Christian Frederick as king of an independent Norway. Independence lasted only months: after a brief war Norway entered a union with Sweden that autumn, but it kept its constitution and its own parliament, the Storting. The Eidsvoll document is still in force, one of the oldest written constitutions in use today, and 17 May is Norway’s national day, celebrated with children’s parades across the country.

Source: Stortinget: The Constitution ↗

1863

Portrait of the Galician poet Rosalía de CastroImage: Luis Sellier · Public domain

culture · Europe

Rosalía de Castro gives Galician its first great book of poems

In the 19th century Galician, the language of north-west Spain, was spoken by most people in the region but seldom written down or printed. Rosalía de Castro changed that with Cantares gallegos, a collection of poems drawing on the songs and speech of country people. Its dedication is dated Santiago, 17 May 1863, the day now taken as its publication. It was the first book printed entirely in Galician, and it launched a literary revival known as the Rexurdimento. A century later, in 1963, the Royal Galician Academy chose 17 May as Día das Letras Galegas, Galician Literature Day, a public holiday in Galicia that each year honours a different writer in the language.

Source: Real Academia Galega: Cantares gallegos (1863) ↗

1865

The ITU’s present-day headquarters buildings in GenevaImage: Bastiaan Quast · CC BY-SA 4.0

world · Europe

Twenty states found the International Telegraph Union in Paris

As telegraph lines spread across borders, every country had its own rules, prices and codes. After two and a half months of talks in Paris, delegates of 20 states signed the first International Telegraph Convention on 17 May 1865, creating the International Telegraph Union. Now the International Telecommunication Union, it is the oldest agency in the United Nations family and still sets shared rules for radio and telecoms.

Source: ITU: The 1865 International Telegraph Conference ↗

1875

An engraving of Aristides, the colt that won the first Kentucky DerbyImage: C. Lloyd · Public domain

sport · Americas

Aristides wins the first Kentucky Derby

Inspired by England’s Epsom Derby, the new Louisville Jockey Club in Kentucky staged a race of its own for three-year-old horses. On 17 May 1875 about 10,000 spectators watched 15 runners set off over a mile and a half at the track later named Churchill Downs. The small chestnut colt Aristides won by two lengths in a record time for the distance. His jockey was 19-year-old Oliver Lewis, a Black rider born in Kentucky, and 13 of the 15 jockeys in the field were Black, a reminder of how central African American horsemen were to early American racing. The Kentucky Derby is now run on the first Saturday in May and is the oldest continuously held major horse race in the United States.

Source: National Museum of Racing and Hall of Fame: Aristides, the original Kentucky Derby hero ↗

THE TWENTIETH CENTURY

The 1900s

War and peace, technological leaps, social change, politics, sport and popular culture.

1900

A Bacon’s war print of the defence of MafekingImage: G W Bacon & Co London · Public domain

world · Africa

The siege of Mafeking is lifted

Early in the South African War, Boer forces surrounded the small British-held town of Mafeking (now Mahikeng) in October 1899. The garrison and townspeople held out for 217 days until a relief column under Colonel Bryan Mahon fought its way in on 17 May 1900. When the news reached Britain the next day, crowds celebrated so wildly that ‘mafficking’ entered the language as a word for riotous rejoicing.

Source: Britannica: Siege of Mafeking ↗

1902

The largest surviving fragment of the Antikythera mechanism, National Archaeological Museum, AthensImage: Logg Tandy · CC BY 4.0

science · Europe

A gear wheel reveals an ancient Greek calculating machine

In 1900 and 1901 sponge divers off the Greek island of Antikythera brought up statues, pottery and other treasures from a Roman-era shipwreck. Among the finds was a shapeless lump of corroded bronze and wood. On 17 May 1902 the archaeologist Valerios Stais, looking over the pieces in Athens, noticed a toothed gear wheel set into one of them, along with traces of Greek writing. It was the first sign that the lump was a machine. Over the following century X-rays and scans showed that the Antikythera mechanism, made more than 2,000 years ago, used dozens of interlocking gears to track the Sun, Moon and planets and to predict eclipses. Nothing of comparable complexity is known again until the astronomical clocks of medieval Europe.

Source: Linda Hall Library: The Antikythera Mechanism ↗

1954

Chief Justice Earl Warren, who delivered the court’s unanimous opinionImage: Harris & Ewing photography firm · Public domain

world · Americas

The US Supreme Court rules school segregation unconstitutional

For more than half a century American law had allowed states to keep Black and white children in separate schools, so long as the schools were supposedly equal. On 17 May 1954 the Supreme Court, speaking through Chief Justice Earl Warren, ruled unanimously in Brown v. Board of Education of Topeka that separate schools were by their nature unequal and broke the Constitution’s promise of equal protection. The case had been brought by Black families in Kansas and several other states, argued by the NAACP lawyer Thurgood Marshall. The ruling overturned the ‘separate but equal’ doctrine of 1896, but change was slow and fiercely resisted in parts of the South. It nonetheless became a cornerstone of the civil rights movement that followed.

Source: National Archives: Brown v. Board of Education (1954) ↗

1983

Beirut on the day of Amine Gemayel’s inauguration as president in 1982Image: James Case from Philadelphia, Mississippi, U.S.A. · CC BY 2.0

politics · Middle East

Israel and Lebanon sign a short-lived withdrawal agreement

A year after Israel invaded Lebanon, talks brokered by the US Secretary of State George Shultz produced an agreement on the withdrawal of Israeli troops. It was signed on 17 May 1983 at Khaldeh in Lebanon and Kiryat Shmona in Israel. Syria and its Lebanese allies opposed it strongly, and under that pressure Lebanon cancelled the agreement in March 1984 without it ever taking effect.

Source: Government of Israel: Agreement between Israel and Lebanon, 17 May 1983 ↗

1990

The World Health Organization’s headquarters at Pregny-Chambésy, GenevaImage: Guilhem Vellut from Annecy, France · CC BY 2.0

world · Global

The WHO stops classing homosexuality as an illness

For decades homosexuality appeared in the International Classification of Diseases, the World Health Organization’s standard list that doctors and health systems across the world use to record illness. On 17 May 1990 the WHO decided to remove it, a decision that took effect in later editions of the classification. The change mattered far beyond medicine, because the label had been used to justify discrimination, so-called cures and criminal laws. In 2004 campaigners chose the anniversary for the International Day Against Homophobia, Biphobia and Transphobia, now marked each 17 May in well over a hundred countries and supported by the European Union and the Council of Europe.

Source: Council of the European Union library: Break the bias, a library guide on unconscious bias and LGBTI ↗

1992

The Democracy Monument on Ratchadamnoen Avenue in Bangkok, where the 1992 protests gatheredImage: Nawit science · CC BY-SA 4.0

politics · Asia

Thai troops open fire on democracy protesters in Bangkok

In April 1992 General Suchinda Kraprayoon, a leader of the previous year’s coup, became Thailand’s prime minister without standing for election, and huge protests followed. On the night of 17 May, after talks on constitutional change broke down, security forces began firing on demonstrators in central Bangkok. Dozens were killed over the following days before the king intervened and Suchinda resigned, opening the way to civilian government.

Source: Human Rights Watch: Bloody May, excessive use of lethal force in Bangkok ↗

1997

A map of the rebel advance across Zaire in the First Congo War, 1996 to 1997Image: Don-kun, Uwe Dedering · CC BY 3.0

world · Africa

Rebel forces take Kinshasa and Zaire becomes the Democratic Republic of the Congo

A day after Mobutu Sese Seko left the capital, troops of Laurent-Désiré Kabila’s rebel alliance marched into Kinshasa on 17 May 1997 after a seven-month campaign across the country. Kabila declared himself president and restored the country’s earlier name, the Democratic Republic of the Congo. Hopes of a fresh start faded quickly, and a far wider war broke out the following year.

Source: US Department of State: Background Note, Congo, Democratic Republic of ↗

RESEARCH

Sources & Further Reading

Selected authoritative references supporting the events on this page.

Catholic Encyclopedia (New Advent): Pope Liberius↗Britannica: Liberius↗The Canadian Encyclopedia: Ville-Marie (Colony)↗Parks Canada: De Maisonneuve, Paul de Chomedey National Historic Person↗Stortinget: The Constitution↗Government of Norway: Norway’s Monarch since 1814↗Real Academia Galega: Cantares gallegos (1863)↗Biblioteca Virtual Miguel de Cervantes: Cantares gallegos↗ITU: The 1865 International Telegraph Conference↗UN News: As International Telecommunication Union turns 150, Ban hails resilience of oldest UN agency↗National Museum of Racing and Hall of Fame: Aristides, the original Kentucky Derby hero↗Britannica: Oliver Lewis↗Britannica: Siege of Mafeking↗South African History Online: The lifting of the siege of Mafeking↗Linda Hall Library: The Antikythera Mechanism↗Wikipedia: Antikythera mechanism↗National Archives: Brown v. Board of Education (1954)↗Britannica: Brown v. Board of Education of Topeka↗Government of Israel: Agreement between Israel and Lebanon, 17 May 1983↗US Office of the Historian: The Reagan Administration and Lebanon, 1981-1984↗Council of the European Union library: Break the bias, a library guide on unconscious bias and LGBTI↗Council of Europe: International Day Against Homophobia, Biphobia and Transphobia 2026↗Human Rights Watch: Bloody May, excessive use of lethal force in Bangkok↗Amnesty International: Thailand, the massacre in Bangkok↗US Department of State: Background Note, Congo, Democratic Republic of↗Britannica: Laurent Kabila↗

WHY THESE MOMENTS?

Significance before volume

This page is not the longest possible list of events. It is a chronological journey through 17 May, where each entry is chosen for historical significance, human interest and reliability.

Facts are checked against authoritative museums, archives, universities and reference works. Where sources disagree, the page says so.

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