Minor naval engagement during the Filibuster War between the Nicaraguan (Filibusters) schooner Granada and the Costa Rican brig Once de Abril, which took place off San Juan del Sur, Nicaragua

Conflict in California in 1856

Last major battle of the Rogue River Wars, in the US

1856 battle of the Dominican War of Independence (1844–1856)

Attack by Native Americans upon Seattle in 1856

1856 Filibuster War battle in Nicaragua

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