In the Roman Catholic Church, the Transfiguration was once celebrated locally in various parts of the Catholic world on different days, including August 6, but was not universally recognized. In 1456, the Kingdom of Hungary repulsed an Ottoman invasion of the Balkans by breaking the siege of Belgrade. News of the victory arrived in Rome on August 6. Given the importance to international politics at that time of such battles between Christian and Muslim nations, in celebration of the victory Pope Callixtus III elevated the Transfiguration to a Feast day to be celebrated in the entire Roman rite.