36day.year
Forces of Emperor Guangwu of the Eastern Han, under the command of Wu Han, conquer the separatist Chengjia empire, reuniting China.
In 36 AD, General Wu Han led Emperor Guangwu’s forces to defeat the Chengjia kingdom, reunifying China under the Eastern Han dynasty.
After decades of civil strife following the fall of the Western Han, Liu Xiu ascended the throne as Emperor Guangwu. Under the command of Wu Han, loyalist troops advanced into Sichuan, the heartland of the breakaway Chengjia empire. By decisively defeating local forces, they ended Chengjia's two-year rule and restored imperial authority. The campaign strengthened central control and paved the way for the Eastern Han’s long period of relative stability. Guangwu’s reunification efforts helped revive agriculture, trade, and Confucian administration across the empire. This victory marked a major turning point in Chinese history, shaping governance and culture for centuries to come.
36
Emperor Guangwu
Eastern Han
Wu Han
Chengjia
274day.year
A temple to Sol Invictus is dedicated in Rome by Emperor Aurelian.
In 274 AD, Emperor Aurelian dedicated a grand temple to Sol Invictus in Rome, promoting the cult of the Unconquered Sun.
In an effort to unify the diverse religious practices of the empire, Emperor Aurelian honored the sun god Sol Invictus with a new temple on the Palatine Hill. The dedication ceremony highlighted the rising prominence of the solar cult among Roman soldiers and citizens. Aurelian's reforms positioned Sol Invictus as a supreme deity, reflecting the emperor’s desire for divine approval and imperial unity. The temple became a focal point for state-sponsored rituals and festivals, influencing later Roman religious traditions. This act also foreshadowed the blending of sun worship with emerging Christian symbolism. The cult of Sol Invictus persisted until the reach of Christianity altered Rome’s spiritual landscape.
274
temple
Sol Invictus
Rome
Aurelian
333day.year
Roman Emperor Constantine the Great elevates his youngest son Constans to the rank of Caesar.
In 333 AD, Constantine the Great appointed his youngest son Constans as Caesar, strengthening dynastic succession.
To secure his dynasty’s future and manage the vast Roman Empire, Emperor Constantine elevated Constans to the rank of Caesar in 333 AD. At only four years old, Constans received the title amid court ceremonies in Constantinople. This move formalized his position as a junior emperor alongside his brothers Constantine II and Constantius II. Constantine's decision aimed to balance power between his heirs and prevent succession disputes. Despite his youth, Constans was groomed for leadership and later governed regions of Gaul and Italy. His elevation reflected the evolving structure of imperial administration in Late Antiquity and set precedents for co-emperorship.
333
Constantine the Great
Constans
Caesar
336day.year
First documentary sign of Christmas celebration in Rome.
In 336 AD, the earliest recorded celebration of Christmas took place in Rome, marking the emergence of December 25th as a Christian feast day.
The Roman calendar of 336 AD provides the first documented reference to December 25th as the Feast of the Nativity. Under Pope Julius I, church officials formalized the celebration to commemorate Christ’s birth. This date was likely chosen to coincide with pagan winter festivals, aiding the transition to Christian worship. The adoption of December 25th spread gradually across the Roman Empire, blending local customs with liturgical observance. Early Christian communities marked the occasion with fasting, prayer, and special Masses. The institutionalization of Christmas on this date laid the foundation for centuries of religious and cultural traditions.
336
Christmas
350day.year
Vetranio meets Constantius II at Naissus (Serbia) and is forced to abdicate his imperial title. Constantius allows him to live as a private citizen on a state pension.
In 350 AD, the usurper Vetranio abdicated his imperial rank before Constantius II at Naissus and was granted a state pension.
After declaring himself emperor with support from Balkan legions, Vetranio met the legitimate ruler Constantius II at Naissus. Facing overwhelming political and military pressure, he chose to surrender his title rather than risk civil war. To secure loyalty and stability, Constantius II permitted him to live as a private citizen on a generous pension. This peaceful resolution prevented further fragmentation of the empire and reinforced the principle of dynastic succession. Vetranio spent his remaining years in retirement, avoiding involvement in later court intrigues. The episode illustrated Constantius's pragmatic approach to dealing with rival claimants during the Constantinian dynasty’s turbulent years.
350
Vetranio
Constantius II
Naissus
Serbia
508day.year
Clovis I, king of the Franks, is baptized into the Catholic faith at Reims, by Saint Remigius.
In 508 AD, Clovis I, King of the Franks, converted to Catholicism at Reims under Saint Remigius, shaping the religious future of the Frankish realms.
After consolidating power among the Frankish tribes, Clovis I sought the support of the Catholic clergy by embracing their faith. On December 25th, 508, he was baptized in a grand ceremony at Reims by Bishop Remigius. The conversion bound the Merovingian dynasty to the Roman Church and distinguished Clovis from other Arian Christian Germanic leaders. This alliance with the Catholic hierarchy strengthened his legitimacy and aided cultural integration within former Roman territories. Clovis's baptism paved the way for the Christianization of the Frankish population. His choice had lasting effects on the religious and political landscape of medieval Europe.
508
Clovis I
Franks
baptized
Catholic
Reims
Saint Remigius
597day.year
Augustine of Canterbury and his fellow-labourers baptise in Kent more than 10,000 Anglo-Saxons.
In 597 AD, Saint Augustine of Canterbury and his companions baptized over 10,000 Anglo-Saxons in Kent, advancing Christian mission in England.
Sent by Pope Gregory the Great, Augustine of Canterbury led the Gregorian Mission to convert England’s pagan tribes. Within weeks of arriving in Kent, Augustine and his fellow missionaries baptized thousands in the River Stour. The mass conversion ceremony at Ebbsfleet involved King Æthelberht of Kent and his court, marking a royal endorsement of Christianity. This event marked a critical turning point for the Christianization of Anglo-Saxon England. Augustine later became the first Archbishop of Canterbury, establishing the ecclesiastical structure that endured for centuries. The mission’s success laid the groundwork for the spread of Roman Christianity throughout the British Isles.
597
Augustine of Canterbury
Kent
Anglo-Saxons
800day.year
The coronation of Charlemagne as Holy Roman Emperor, in Rome.
On Christmas Day 800, Pope Leo III crowned Charlemagne as the first Holy Roman Emperor in Rome, reviving the imperial title in the West.
Charlemagne, King of the Franks and Lombards, journeyed to Rome to aid and defend Pope Leo III. On December 25th, 800, during Mass at St. Peter's Basilica, the pope placed a golden crown on Charlemagne’s head and proclaimed him Emperor of the Romans. This coronation revived the idea of a unified Christian empire in Western Europe after centuries of Roman decline. The event symbolized the alliance between the papacy and the Frankish kingdom and enhanced Charlemagne’s prestige. It laid the ideological foundation for what would become the Holy Roman Empire. While Charlemagne accepted the title with some surprise, he used it to legitimize his authority and codify his rule over vast territories.
800
Charlemagne
Holy Roman Emperor
820day.year
Eastern Emperor Leo V is murdered in a church of the Great Palace of Constantinople by followers of Michael II.
In 820 AD, Emperor Leo V was assassinated in a chapel of the Great Palace in Constantinople by agents of Michael II, triggering a dynastic change.
Leo V 'the Armenian' had ruled the Byzantine Empire during a period of iconoclast controversy and military challenges. On December 25th, 820, during a Christmas Eve service in the chapel of the Great Palace, he was violently murdered by conspirators loyal to Michael the Amorian. Michael II, his former protégé, seized power immediately after the assassination and was crowned emperor days later. The regicide shocked Constantinople, highlighting the volatility of Byzantine court politics. Leo's death ended his attempts to restore iconoclasm and reopened tensions over religious imagery in the empire. The transition of power through murder underscored the lethal stakes of imperial succession in Byzantium.
820
Leo V
church
Great Palace
Constantinople
Michael II
1000day.year
The foundation of the Kingdom of Hungary: Hungary is established as a Christian kingdom by Stephen I of Hungary.
In 1000 AD, Stephen I was crowned the first King of Hungary, establishing Hungary as a Christian realm in Central Europe.
Stephen I, originally Grand Prince of the Magyars, adopted the crown sent by Pope Sylvester II to solidify his realm’s Christian credentials. On December 25th, 1000, at Esztergom, he received the royal title and invested bishops, creating a national church hierarchy. His reign initiated the conversion of Magyar tribes from paganism to Catholicism. Stephen’s reforms included granting lands to the Church and promoting Western European institutions, monasteries, and schools. He laid the administrative foundations of the medieval Hungarian state and fostered alliances with neighboring powers. The establishment of the Kingdom of Hungary helped shape the political map of Europe for centuries. After his death, Stephen was canonized, becoming Hungary’s patron saint and inspiring national identity.
1000
Kingdom of Hungary
Stephen I of Hungary
1013day.year
Sweyn Forkbeard takes control of the Danelaw and is proclaimed king of England.
On December 25, 1013, Sweyn Forkbeard seized the Danelaw and was proclaimed king of England, marking the first Danish rule over the realm.
In 1013, the Danish warlord Sweyn Forkbeard launched a decisive campaign into England, capturing the northern territories known as the Danelaw.
On Christmas Day, local leaders recognized his authority and proclaimed him king, ending Æthelred the Unready's reign.
This event represented the zenith of Viking power in England and set the stage for a brief period of Danish rule.
Although Sweyn died just months later, his conquest underscored the shifting balance between Anglo-Saxon and Scandinavian influences.
The proclamation at York cemented his legacy as the first Danish monarch of a united English kingdom.
1013
Sweyn Forkbeard
Danelaw
England
1025day.year
Coronation of Mieszko II Lambert as king of Poland.
Mieszko II Lambert was crowned king of Poland on December 25, 1025, succeeding his father and reinforcing the newly established crown.
Mieszko II Lambert, the son of Bolesław I the Brave, ascended to the Polish throne and received his crown on Christmas Day 1025.
His coronation at Gniezno marked the continuity of Poland's royal dynasty and the recognition of its sovereignty by church authorities.
Under his rule, the kingdom faced internal rebellions and external pressures from neighboring states.
Despite later challenges to his authority and temporary exile, Mieszko II's reign was a key link in consolidating the medieval Polish monarchy.
His crowning symbolized the growing importance of Poland in Central European politics.
1025
Mieszko II Lambert