The First Council of Nicaea is formally opened, starting the first ecumenical council of the Christian Church.

First Council of NicaeaEcumenical council

Empress Ariadne marries Anastasius I. The widowed Augusta is able to choose her successor for the Byzantine throne, after Zeno (late emperor) dies of dysentery.

Ariadne (empress)Anastasius I DicorusAugusta (honorific)Byzantine EmpireZeno (emperor)

An earthquake kills about 250,000 people in what is now Syria and Antiochia.

526 Antioch earthquakeSyriaAntioch

The Battle of Dun Nechtain is fought between a Pictish army under King Bridei III and the invading Northumbrians under King Ecgfrith, who are decisively defeated.

Battle of Dun NechtainPictsBridei IIINorthumbriansEcgfrith of Northumbria

King Æthelberht II of East Anglia visits the royal Mercian court at Sutton Walls, with a view to marrying princess Ælfthryth. He is taken captive and beheaded.

Æthelberht II of East AngliaMerciaSutton Walls Hill FortÆlfthryth of CrowlandDecapitation

The Second Battle of Lincoln is fought near Lincoln, England, resulting in the defeat of Prince Louis of France by William Marshal, 1st Earl of Pembroke.

Second Battle of LincolnLincoln, EnglandLouis VIII of FranceWilliam Marshal, 1st Earl of Pembroke

King Sancho IV of Castile creates the Estudio de Escuelas de Generales in Alcalá de Henares.

Sancho IV of CastileEstudio de Escuelas de GeneralesAlcalá de Henares

The Battle of Alfarrobeira is fought, establishing the House of Braganza as a principal royal family of Portugal.

Battle of AlfarrobeiraHouse of Braganza

John Cabot sets sail from Bristol, England, on his ship Matthew looking for a route to the west (other documents give a May 2 date).

John CabotBristolMatthew (ship)May 2

Portuguese explorer Vasco da Gama discovers the sea route to India when he arrives at Kozhikode (previously known as Calicut), India.

Vasco da GamaDiscovery of the sea route to IndiaKozhikode

The massacre at the festival of Tóxcatl takes place during the Fall of Tenochtitlan, resulting in turning the Aztecs against the Spanish.

Massacre in the Great TempleFall of Tenochtitlan

Ignatius of Loyola is seriously wounded in the Battle of Pampeluna.

Ignatius of LoyolaBattle of Pampeluna

Cartographer Abraham Ortelius issues Theatrum Orbis Terrarum, the first modern atlas.

CartographyAbraham OrteliusTheatrum Orbis TerrarumAtlas

Shakespeare's sonnets are first published in London, perhaps illicitly, by the publisher Thomas Thorpe.

Shakespeare's sonnetsThomas Thorpe

The city of Magdeburg in Germany is seized by forces of the Holy Roman Empire and most of its inhabitants massacred, in one of the bloodiest incidents of the Thirty Years' War.

MagdeburgHoly Roman EmpireSack of MagdeburgThirty Years' War

Yangzhou massacre: the 10-day massacre of 800,000 residents of the city of Yangzhou, part of the Transition from Ming to Qing.

Yangzhou massacreYangzhouTransition from Ming to Qing

The controversial Mecklenburg Declaration of Independence is allegedly signed in Charlotte, North Carolina.

Mecklenburg Declaration of IndependenceCharlotte, North Carolina

By the Law of 20 May 1802, Napoleon Bonaparte reinstates slavery in the French colonies, revoking its abolition in the French Revolution.

Law of 20 May 1802Napoleon BonaparteSlaveryFrench colonial empireFrench Revolution

Napoleon Bonaparte leads his French troops into the Battle of Bautzen in Saxony, Germany, against the combined armies of Russia and Prussia. The battle ends the next day with a French victory.

Battle of BautzenSaxonyPrussia

York Minster is badly damaged by fire.

York Minster

American Civil War: The state of Kentucky proclaims its neutrality, which will last until September 3 when Confederate forces enter the state. Meanwhile, the State of North Carolina secedes from the Union.

American Civil WarKentuckyCountry neutrality (international relations)September 3Confederate States of America

U.S. President Abraham Lincoln signs the Homestead Act into law.

Abraham LincolnHomestead Act

American Civil War: Battle of Ware Bottom Church: In the Virginia Bermuda Hundred Campaign, 10,000 troops fight in this Confederate victory.

Battle of Ware Bottom ChurchVirginiaBermuda Hundred Campaign

Levi Strauss and Jacob Davis receive a U.S. patent for blue jeans with copper rivets.

Levi StraussJacob W. DavisPatentJeansCopper

Signing of the Metre Convention by 17 nations leading to the establishment of the International System of Units.

Metre ConventionInternational System of Units

The Triple Alliance between the German Empire, Austria-Hungary and the Kingdom of Italy is formed.

Triple Alliance (1882)Austria-HungaryKingdom of Italy

Krakatoa begins to erupt; the volcano explodes three months later, killing more than 36,000 people.

Krakatoa1883 eruption of Krakatoa

History of cinema: The first public display of Thomas Edison's prototype kinetoscope.

History of filmThomas EdisonKinetoscope

Cuba gains independence from the United States. Tomás Estrada Palma becomes the country's first President.

CubaTomás Estrada Palma

Treaty of Jeddah: The United Kingdom recognizes the sovereignty of King Ibn Saud in the Kingdoms of Hejaz and Nejd, which later merge to become the Kingdom of Saudi Arabia.

Treaty of Jeddah (1927)SovereigntyIbn SaudHejazNajd