At the same time, there were many free African Americans in the north. Unlike slaves, they were allowed to start churches, write newspapers, and sometimes own property. Frederick Douglass was an important abolitionist (fighter against slavery). Harriet Tubman helped to create the Underground Railroad, which helped African Americans to sneak away from their masters and become free. During the American Civil War from 1861-1865, the south broke away from the United States to form the Confederate States of America, or Confederacy. The United States won the war, and in 1865, it freed all slaves (about 4 million) by the 13th amendment.