The First Congress of Vienna was held in 1515, attended by the Holy Roman Emperor, Maximilian I, and the Jagiellonian brothers, Vladislaus II, King of Hungary and King of Bohemia, and Sigismund I, King of Poland and Grand Duke of Lithuania. Previously, Vladislaus and Maximilian had agreed on a Habsburg-Jagiellon mutual-succession treaty in 1506. It became a turning point in the history of Central Europe. After the death of Vladislaus, and later his son and heir, the childless King Louis II at the Battle of Mohács against the Ottomans in 1526, the Habsburg-Jagellion mutual succession treaty ultimately increased the power of the Habsburgs and diminished that of the Jagiellonians.