I believe the major cause of the Civil War was the Compromise of 1850. California was admitted in as a free territory, which causes tension in law making. The Fugitive Slave Act involves Northerners in the institution of slavery because the government is forced to get involved.
Fort Sumter is the first battle of the Civil War. Only one guy dies on the Union side. This battle ended with a Confederate victory.
At this point of the war, Antietam was the bloodiest day of the war. The Union won this battle and the Emancipation Proclamation was said, which freed all slaves not controlled by the Union.
Gettysburg was the turning point of the war. Pickett's Charge happened too, which was where there were 7,000 casualties in less than 30 minutes. Abraham Lincoln also gave one of his famous speeches, the Gettysburg Address.