Events leading to the Civil War First African America n Slaves arrive in Virginia in 1619 Missouri Compromise 1820 adds two states Maine and Missouri as well as 36.30 Northwest Ordinance of 1787 establishes Ohio River as boundary of Free and Slave States Michael DeLeo Social Studies Uncle Tom's Cabin Written by Harriet Beecher Stowe in 1852 1836 Congress enacts "Gag Rule" Nat Turner Slave revolt in 1831 leads to stricter rules against slaves. Compromise of 1850. Also known as the compromise that pleased no one. Abraham Lincoln elected Presiden t 1860 Dred Scott Supreme Court decision allows slavery in all the territories 1857 May 3, 2012 1st Period Confeder ates fire on Fort Sumter to start the Civli War April 12, 1861 Events leading to the Civil War Michael DeLeo Social Studies May 3, 2012 1st Period