Bleeding Kansas was a border war on the Kansas-Missouri border. It started with the Kansas–Nebraska Act of 1854. It continued into the American Civil War (1854–1861).[2] It was an ugly war between groups of people who had strong beliefs about slavery.[3] The term was first coined by Horace Greeley of the New York Tribune.[4] He used it to describe the violence happening in the Kansas territory during the mid to late 1850s.[4] Three different groups were fighting for power in Kansas at the time. These were those who were pro-slavery, abolitionists and free-staters.[2] Bleeding Kansas, fought over the issue of slavery, was a precursor of events to come in the American Civil War.