2 July — The Russian army invades the Principality of Moldavia — the Crimean War begins.
24 August — Potato chips are invented by the American George Crum.
4 October — Russian Admiral Gennady Nevelskoy raised the Russian flag on Sakhalin.
19 November — The Battle of Bashkadyklar took place near the Turkish village of Bashkadyklar, in which Russian troops (about 10,000 men, 32 guns) defeated the forces of Ahmed Pasha (36,000 men, 46 guns) during the Crimean War of 1853–1856. The plan of the Anglo-French-Turkish coalition to seize the Caucasus was thwarted.
30 November — The Battle of Sinop, a naval engagement during the Crimean War, in which a Russian squadron under Vice Admiral Pavel Nakhimov crushed a numerically superior Turkish squadron and secured Russian naval dominance in the Black Sea.