150 years ago this week marks the start of what many experts agree is probably the real start to the U.S. Civil War - the Border War between Missouri and Kansas. Historians trace the roots of the conflict back to the earliest days of the young United States, the Northwest Ordinance of 1787. That act would establish states south of the Ohio River would be slave-holding ones, while those north would be free. That balance would hold until after the Louisiana Purchase when Missourians would petition to enter the union. Many wanted to see Missouri as a slave-holding state, despite the fact that it sat above that Ohio River line. Virgil Dean, research historian with the Kansas State Historical Society in Topeka says the Missouri Compromise of 1820 would try to settle that dispute. Everything within the Louisiana Purchase territory north of Missouri's southern border would be free. Missouri would be the lone exception until more compromises later would introduce the idea that the people in each new state could decide if they wanted to be slave or free. That concept of popular sovereignty would be put to the test in the newly formed Kansas Territory in 1854 as each side used trickery, election rigging, and all out war to keep the other from getting what they wanted the Border War between Missouri and Kansas.