- March 4, 1853 – Pierce becomes the 14th president
- 1854 – Gadsden Purchase from Mexico
- 1854 – Kansas–Nebraska Act; nullified Missouri Compromise
- 1854 – Ostend Manifesto
- 1854 – Whig Party collapses
- 1854 – Treaty of Kanagawa with Japan
- 1854-1855 Know-Nothing Party, mushroom growth and sudden collapse
- 1856 – Sack of Lawrence, Kansas
- 1856 – Pottawatomie massacre
- 1856 – U.S. presidential election,
- 1856: James Buchanan elected president March 4,
- 1857 – Buchanan becomes the 15th president;
- 1857 – Dred Scott v. Sandford 60 US 393
- 1857 declares that slaves and Blacks descended from slaves were not American citizens and cannot sue
- 1857 – Utah War
- 1857 – Lecompton Constitution rejected in Kansas Territory
- 1857 – Panic of 1857