May 20
Overview
Holidays & Observances
Christianfeast day:
Abercius and Helena, Alcuin of York, Aurea of Ostia, Austregisilus, Baudilus, Bernardino of Siena, Ivo of Chartres, Lucifer of Cagliari, Sanctan, May 20 (Eastern Orthodox liturgics)
An Eastern Orthodox liturgical feast commemorating saints such as Abercius and Helena on May 20.
Day of Remembrance (Cambodia)
A Cambodian national holiday honoring the victims of the Khmer Rouge regime.
Emancipation Day (Florida)
A Florida state holiday commemorating the emancipation of enslaved people in 1865.
European Maritime Day(European Council)
European Union observance highlighting the importance of maritime activities for trade and economy.
Independence Restoration Day, celebrates the independence ofEast TimorfromIndonesiain 2002.
East Timor’s holiday marking restoration of its independence from Indonesia in 2002.
Josephine Baker Day(NAACP)
NAACP commemorative day honoring Josephine Baker’s legacy as an entertainer and civil rights activist.
National Awakening Day(Indonesia), and its related observances:
Indonesian Doctor Day(Indonesia)
In Indonesia, May 20 honors the 1908 National Awakening movement and also celebrates Indonesian Doctor Day.
National Day (Cameroon)
Cameroon’s Unity Day celebrates the national reunification achieved on May 20, 1972.
World Bee Day
United Nations day to raise awareness about the crucial role of bees in ecosystems and agriculture.
Events
The First Council of Nicaea is formally opened, starting the first ecumenical council of the Christian Church.
The First Council of Nicaea convenes under Emperor Constantine, marking the first unified gathering of Christian bishops.
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.
Empress Ariadne of Byzantium marries Anastasius I, securing the imperial succession after Zeno’s death.
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.
Pictish forces under Bridei III rout King Ecgfrith’s Northumbrian army at Dun Nechtain, preserving Pictish independence.
While visiting the royal Mercian court at Sutton Walls with a view to marrying princess Ælfthryth, King Æthelberht II of East Anglia is taken captive and beheaded.
King Æthelberht II of East Anglia is seized and executed at Sutton Walls, ending his dynasty’s ambitions.
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.
William Marshal leads royalist forces to victory over Prince Louis at the Second Battle of Lincoln, tipping the balance in the First Barons’ War.
King Sancho IV of Castile creates the Estudio de Escuelas de Generales in Alcalá de Henares.
King Sancho IV of Castile founds the Estudio de Escuelas de Generales in Alcalá de Henares, an early center for higher learning.
King Mohnyin Thado formally ascends to the throne of Ava.
Mohnyin Thado is crowned king of the Ava Kingdom, initiating a period of consolidation in Upper Burma.
The Battle of Alfarrobeira is fought, establishing the House of Braganza as a principal royal family of Portugal.
Supporters of King Afonso V defeat Infante Peter at Alfarrobeira, elevating the House of Braganza in Portugal.
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).
Explorer John Cabot departs Bristol aboard the Matthew, embarking on a westward quest for Asia.
Births
Bonne of Luxembourg
Queen consort of France as the first wife of King John II and daughter of Holy Roman Emperor Henry VII.
Pietro Bembo
Italian cardinal, poet, and humanist scholar who played a pivotal role in shaping Renaissance culture and the Italian language.
Levinus Lemnius
Dutch physician and author known for his influential works on natural philosophy and human physiology.
Thado Minsaw of Ava
Viceroy of Ava who governed Upper Burma under the Toungoo dynasty and strengthened imperial administration.
Hieronymus Fabricius
Italian anatomist and surgeon whose pioneering studies of the venous system and embryology advanced modern anatomical science.
Robert Heath
English judge and politician who served as Chief Justice of the Common Pleas in the early Stuart period.
Andreas Schlüter
German Baroque sculptor and architect renowned for his monumental works in Berlin and at the Prussian court.
Francis Cotes
English portrait painter and pastel artist who was a founding member of the Royal Academy.
William Thornton
Virgin Islander-American architect, physician, and inventor best known for designing the United States Capitol.
Deaths
Ecgfrith was King of Northumbria from 670 until his death in 685. He is remembered for his military campaigns and his role in shaping early medieval Britain.
Æthelberht II
Anglo-Saxon king of East Anglia in the late 8th century, revered as a saint and martyr.
Gero the Great
Powerful Saxon margrave who expanded border defenses and led campaigns against Slavic tribes.
Bao Zheng
Song dynasty official celebrated for his integrity and strict administration of justice.
Portuguese scholar and physician who became Pope in 1276 and served until his death in 1277.
King of Cyprus in 1285 whose brief reign reflected the island’s complex Crusader heritage.
13th-century Sufi saint from Bukhara renowned for his spiritual teachings in South Asia.
Maria of Calabria
An Angevin princess who held the title Empress of Constantinople in the mid-14th century.
Bernardino of Siena
Franciscan missionary and preacher whose charismatic sermons led to widespread devotion.