* The Compromise of 1850 is passed, which temporarily resolves the issue of slavery in the territories acquired from Mexico.
* The Fugitive Slave Act is passed, which requires all citizens to return escaped slaves to their owners.
* California is admitted to the Union as a free state.
1851:
* The first World's Fair is held in London.
* Herman Melville publishes Moby-Dick.
1852:
* Louis Napoleon Bonaparte becomes emperor of France.
* Harriet Beecher Stowe publishes Uncle Tom's Cabin, which becomes a bestseller and helps to increase support for the abolition of slavery.
1853:
* Commodore Matthew Perry leads an American naval expedition to Japan, which forces Japan to open its ports to American trade.
* Russia sells Alaska to the United States for $7.2 million.
1854:
* The Crimean War begins between Russia and an alliance of Britain, France, and the Ottoman Empire.
* The Republican Party is founded in the United States.
1855:
* Florence Nightingale leads a team of nurses to Crimea to care for wounded soldiers.
* David Livingstone becomes the first European to reach Victoria Falls in Africa.
* Walt Whitman publishes Leaves of Grass.
1856:
* The Crimean War ends with the signing of the Treaty of Paris.
* The first Bessemer steel is produced.
1857:
* The Indian Mutiny begins against British rule in India.
* The Dred Scott decision is handed down by the U.S. Supreme Court, which rules that African Americans are not citizens and cannot sue in federal court.
* The financial Panic of 1857 begins in the United States.
1858:
* Abraham Lincoln and Stephen Douglas debate slavery in a series of seven debates in Illinois.
* Charles Darwin publishes On the Origin of Species, which introduces his theory of evolution.
1859:
* John Brown leads a raid on Harpers Ferry, Virginia, in an attempt to start a slave rebellion.
* The first oil well is drilled in Titusville, Pennsylvania.