The American Civil War was a conflict fought from 1861 to 1865 between the northern states, known as the Union, and the southern states that seceded to form the Confederacy. The war primarily centered around issues such as slavery, states' rights, and economic differences. The war resulted in significant loss of life and widespread destruction. Key battles included Gettysburg and Antietam, and notable figures included Abraham Lincoln for the Union and Jefferson Davis for the Confederacy. The conflict ultimately led to the preservation of the Union and the abolition of slavery in the United States.