1409 CE
A year defined by the Council of Pisa's failed attempt to resolve the Western Schism by electing a third pope, the founding of the University of Leipzig, and the continued fragmentation of the Ottoman Empire during the Interregnum.
Geopolitics & Diplomacy
- The Council of Pisa convened in March to resolve the Western Schism, attracting cardinals, bishops, and theologians from across Christendom.
- The Council of Pisa deposed both Pope Gregory XII and Antipope Benedict XIII, but neither accepted the ruling, leaving three rival popes.
- The Council of Pisa elected Alexander V as a new pope, creating a three-way schism that further complicated the governance of the Catholic Church.
- The Treaty of Bicêtre temporarily reconciled the Armagnac and Burgundian factions in France, though the peace would prove fragile.
- The Republic of Venice expanded its mainland territories in northeastern Italy, acquiring the city of Padua and strengthening its position on the terraferma.
- The Kingdom of Poland and the Grand Duchy of Lithuania formalized military cooperation against the Teutonic Knights in anticipation of future conflict.
Conflict & Security
- Owen Glendower's revolt was reduced to guerrilla resistance as the Welsh rebel leader lost control of his remaining castles and territories.
- Musa Çelebi extended his control across the Ottoman European provinces, threatening Byzantine Constantinople and pressuring Serbian vassals.
- Mehmed Çelebi in Anatolia prepared for a final confrontation with Musa Çelebi to reunify the Ottoman Empire under a single ruler.
- English forces completed the recapture of Aberystwyth Castle, further reducing Owen Glendower's military capacity in Wales.
- Teutonic Knight forces raided Lithuanian territories, provoking retaliatory strikes and deepening hostilities ahead of a major confrontation.
- Venetian expansion on the Italian mainland brought the republic into conflict with neighboring powers, including Verona and the Duchy of Milan.
- The Ming military launched expeditions against Mongol and Jurchen groups along the northern and northeastern frontiers of the empire.
Economy & Finance
- Zheng He's fleet returned from its second voyage, bringing tribute goods and diplomatic presents from rulers across the Indian Ocean world.
- The Council of Pisa attracted thousands of clerics and their retinues to the city, temporarily boosting the local economy with their expenditures.
- Venetian territorial expansion on the Italian mainland brought new agricultural lands and tax revenues under the republic's control.
- Mining operations in the German lands expanded, with increasing production of silver, copper, and iron ore from deposits in Saxony and Bohemia.
Technology & Infrastructure
- Construction of the Forbidden City in Beijing continued to advance, with work on the grand ceremonial halls and imperial residences progressing.
- Advances in printing technology in Korea continued, with metal movable type used to produce government documents and Buddhist texts.
Science & Discovery
- The University of Leipzig was founded after a migration of German-speaking scholars from the University of Prague, becoming a major center of learning.
- The Council of Pisa brought together scholars from across Europe, facilitating intellectual exchange and debate on theology, law, and philosophy.
- Ulugh Beg in Samarkand advanced his plans for a major astronomical observatory, gathering scholars and instruments for systematic celestial observation.
Health & Medicine
- The Council of Pisa brought large numbers of people into close quarters, raising concerns about disease transmission among the assembled clergy.
Climate & Environment
- Atmospheric carbon dioxide concentration was approximately 272 parts per million, as later confirmed by ice core analysis.
Culture & Society
- The founding of the University of Leipzig created a new intellectual center in Saxony, attracting scholars and students from across the German-speaking world.
- The Council of Pisa stimulated debate about Church reform and the proper governance of Christendom among educated clerics and laypeople.
- The estimated world population was approximately 360 million.