After winning the Battle of Vienna, the Holy League gained the upper hand and reconquered Hungary (Buda and Pest were retaken in 1686, the former under the command of a Swiss-born convert to Islam). At the same time, the Venetians launched an expedition into Greece, which conquered the Peloponnese. During the 1687 Venetian attack on the city of Athens (conquered by the Ottomans), the Ottomans turned the ancient Parthenon into an ammunitions storehouse. A Venetian mortar hit the Parthenon, detonating the Ottoman gunpowder stored inside, partially destroying it.