The American civil war was a conflict that took place in the United States from 1861-1865, between the Northern States that remained loyal to the Union and the Southern states that had seceded to establish the Confederate States of America. The long-running debate about the enslavement of African-American people was the key cause of the start of the American Civil War. Just over a month after Abraham Lincoln took office as President of the United States, Confederate forces assaulted Fort Sumter in South Carolina in April 1861, sparking the start of the American Civil War.
The Union loyalists in the North, which included some geographically western and southern states, declared their support for the Constitution. They were opposed by Confederate States of America secessionists in the South, who campaigned for states' rights to keep slavery. One of the first industrial conflicts was the American Civil War. There was considerable use of steamships, railroads, the telegraph, and manufactured weapons. Civilian factories, mines, shipyards, banking, transportation, and food supplies were all mobilized, which hinted to the effects of industrialization in World Wars I and II as well as later wars. The conflict continues to be the deadliest in American history. Historically, it has been estimated that 620,000 people died between 1861 and 1865, however a new study contends that 750,000 troops as well as an unknown number of civilians perished.
The American Civil War had a significant impact on the identity of the United States. The triumph of the Union saved the country from splitting apart and resulted in the freedom of four million African slaves. With the passage of the Thirteenth Amendment to the United States Constitution in December 1865, slavery was formally abolished. The Reconstruction Era, which lasted from 1865 to 1877 and saw the reintegration of the Confederate states into the Union, the emancipation of African Americans, and the establishment of the Civil War's legacy, followed the war. Reconstruction's unresolved problems, such as the ongoing discrimination against African Americans, surfaced during the civil rights movement of the 1950s and 1960s.