1439

1439 was a year in the 15th century notable for religious diplomacy within Europe, during a period of fragmented political authority and cultural change. It fell within the broader context of the late medieval world, when the Catholic Church played a central role in politics, education, and international affairs, and when European powers were gradually expanding through trade and exploration.

The principal event associated with 1439 was the culmination of the Council of Florence (Ferrara-Florence), which had begun in 1438 as an effort to reunite the Roman Catholic Church and the Eastern Orthodox Church after the Great Schism. In 1439, a Decree of Union was proclaimed, presenting an agreement on doctrinal matters such as the authority of the pope and certain creedal formulations, including the Filioque clause. The Byzantine delegation, led by prominent church leaders and Imperial authorities, supported the effort during the council. However, the union did not secure lasting acceptance in the Eastern Christian world and was largely reversed in the following decades.

Beyond the council, 1439 stood in a period of ongoing regional conflicts and shifting alliances in Europe. The era also foreshadowed later cultural and technological developments, such as the spread of printed texts, which would accelerate in the subsequent decades and contribute to the broader changes of the Renaissance. The events of 1439 thus reflect both the attempt to heal medieval divisions and the continuing divergence that characterized the period.