January 1, 1815
Congress of Vienna — conference of ambassadors of European states (September/November 1814 to June 1815)
1815 eruption of Mount Tambora — catastrophic volcanic eruption in present-day Indonesia
Unification of Italy — creation of the politically and administratively integrated nation of Italy (1815–1871)
1815 treaties between the United States and Algeria
Capture of HMS Cyane
Battle of the Neapolitan War
Second Serbian Uprising — 1815–1817 revolt in Serbia against the Ottoman Empire
1815 siege during the Neapolitan War
1815 conflict of the Napoleonic Wars
1815 treaty between Naples and Austria