The Civil War was fought between the American states. The argument was over statesΓÇÖ rights to make their own decisions, including whether or not to own slaves. Some of the southern states began to secede (leave) the Union. They formed the Confederate States of America.
In 1780, Massachusetts became the first state to end slavery. Many of the people in Massachusetts were abolitionists, and some offered their homes as stops on the Underground Railroad which allowed slaves to escape to Canada. About 150,000 Massachusetts troops participated in the war from 1861 to 1865.
