America in the 1800s By gabrielas Period: Jan 1, 1800 to Jan 1, 1851 America in the 1800s Jan 1, 1820 Abolitionist Reform Movement Begins Period: Jan 1, 1820 to Dec 31, 1870 Abolitionist Movement Dec 29, 1845 Texas Annexed to US Apr 25, 1846 Mexican-American War Started Jan 24, 1848 California Gold Rush Begins Feb 2, 1848 Treaty of Guadalupe-Hidalgo Signed (Mexican-American War Ends) Apr 21, 1861 Civil War Begins
