December 21
Overview
Holidays & Observances
Armed Forces Day(Philippines)
A national day in the Philippines honoring the founding and service of the Armed Forces of the Philippines, celebrated annually on December 21.
Christianfeast day:
O Oriens, Peter Canisius, Thomas the Apostle, December 21 (Eastern Orthodox liturgics)
A Christian observance on December 21 marking the feast of several saints, including the Advent antiphon 'O Oriens', Saint Peter Canisius, and Saint Thomas the Apostle across Western and Eastern traditions.
Forefathers' Day(Plymouth, Massachusetts)
A local observance in Plymouth, Massachusetts, celebrating the 1620 landing of the Pilgrims with parades and historical ceremonies held annually on December 21.
São Tomé Day(São Tomé and Príncipe)
A national holiday in São Tomé and Príncipe commemorating the discovery of the island by Portuguese explorers on December 21, 1471.
O Oriens
The seventh of the O Antiphons sung during Vespers in the week before Christmas, observed on December 21.
Peter Canisius
The feast day of Saint Peter Canisius, a 16th-century Jesuit priest and Doctor of the Church, observed on December 21.
Thomas the Apostle
The traditional Western feast day of Saint Thomas the Apostle, commemorating his mission and testimony, observed on December 21.
December 21 (Eastern Orthodox liturgics)
In Eastern Orthodox Christianity, December 21 marks the Forefeast of the Nativity and various saint commemorations during the Nativity Fast.
Events
The Roman Senate declares Vespasian emperor of Rome, the last in the Year of the Four Emperors.
The Roman Senate proclaims Vespasian as emperor in AD 69, concluding the Year of the Four Emperors and ushering in the Flavian dynasty.
Pope Honorius II is consecrated, having been elected after the controversial dethroning of Pope Celestine II.
Pope Honorius II is consecrated in 1124, following the contentious removal of Pope Celestine II.
After a siege of several weeks, the city of Weinsberg and its castle surrender to Conrad III of Germany.
After a weeks-long siege, the city of Weinsberg surrenders to Conrad III of Germany in 1140.
The city of Ryazan is sacked by the Mongol army of Batu Khan.
Batu Khan’s Mongol army sacks the Russian city of Ryazan in 1237, marking the start of the Mongol invasion of Rus'.
The Battle of Linuesa is fought in the context of the Spanish Reconquista between the forces of the Emirate of Granada and the combined army of the Kingdom of Castile and of Jaén resulting in a Castilian victory.
The Battle of Linuesa in 1361 sees Castilian forces defeat the Emirate of Granada during the Reconquista.
Battle of Curalaba: The revolting Mapuche, led by cacique Pelentaru, inflict a major defeat on Spanish troops in southern Chile.
The Mapuche, led by Pelentaru, deal a major defeat to Spanish troops at the Battle of Curalaba in 1598.
Plymouth Colony: William Bradford and the Mayflower Pilgrims land near what is now known as Plymouth Rock in Plymouth, Massachusetts.
William Bradford and the Mayflower Pilgrims land at Plymouth Rock, establishing Plymouth Colony in 1620.
American settlers in Nacogdoches, Mexican Texas, declare their independence, starting the Fredonian Rebellion.
American settlers in Nacogdoches declare independence, igniting the Fredonian Rebellion in Mexican Texas, 1826.
Egyptian–Ottoman War: Egyptian forces decisively defeat Ottoman troops at the Battle of Konya.
Egyptian forces under Ibrahim Pasha defeat the Ottomans at the Battle of Konya in 1832.
Births
Minamoto no Yorinobu
Heian period Japanese samurai renowned for his leadership and martial skill.
Masaccio
Pioneering Italian Renaissance painter known for groundbreaking use of perspective and naturalism.
William Conyers
English nobleman and 1st Baron Conyers who played a notable role in Tudor-era aristocracy.
Thomas Wriothesley
1st Earl of Southampton, influential English statesman and Lord Chancellor under Henry VIII.
Luigi d'Este
Prominent Catholic cardinal of the House of Este, noted for his influence during the Counter-Reformation.
Thomas Allen
English scholar, mathematician, and astrologer who preserved ancient manuscripts and advanced scientific thought.
Man Singh I
Rajput ruler and trusted Mughal general known for military leadership and diplomacy under Emperor Akbar.
Peter Mohyla
Ruthenian Orthodox metropolitan and saint who reformed the church and founded Kyiv-Mohyla Academy.
Roger Williams
Founder of Rhode Island and advocate for religious freedom and separation of church and state.
Deaths
Thomas the Apostle
One of the Twelve Apostles of Jesus, known for his missionary work and martyrdom in India.
Hincmar
Influential 9th-century Archbishop of Reims who shaped Carolingian politics and church governance.
Sun Sheng
Chinese chancellor during the tumultuous Five Dynasties and Ten Kingdoms period, known for his governance.
Al-Mu'izz
Fourth Fatimid Caliph who conquered Egypt and founded the city of Cairo in the 10th century.
Hugh of Tuscany
Italian margrave of Tuscany in the late 10th century, defender of Papal territories.
Ali ibn Muhammad ibn al-Walid
A Dāʿī al-Muṭlaq of the Tayyibi Isma'ili sect, guiding the community in the early 13th century.
Henry I
First Landgrave of Hesse who established its independence in the late 13th century.
Thomas Hemenhale
Medieval Bishop of Worcester known for his administrative reforms in the English Church.
Constantine III
King of the Armenian Kingdom of Cilicia whose reign saw political struggles in the 14th century.