March 20, 1856
Last major battle of the Rogue River Wars, in the US
Conflict in California in 1856
1856 battle of the Dominican War of Independence (1844–1856)
Attack by Native Americans upon Seattle in 1856
Treaty of Paris — 1856 treaty
1856 riot in Panama City
Unequal treaty in modern-day Thailand
1856 battle during the Bleeding Kansas era
Earthquakes in northern Algeria
1856–1860 war between British–French forces and China