<P> To a large extent, the American Civil War was fought in cities and farms of Tennessee, as only Virginia saw more battles . However, Tennessee is the only state to have major battles or skirmishes fought in every single county . Tennessee was the last of the Southern states to declare secession from the Union as a substantial portion of the population were against secession, but saw more than its share of the devastation resulting from years of warring armies criss - crossing the state . Its rivers were key arteries to the Deep South, and, from the early days of the war, Union efforts focused on securing control of those transportation routes, as well as major roads and mountain passes such as the Cumberland Gap . Tennessee was also considered "the Bread Basket" of the Confederacy, for its rich farmland that fed both armies during the war . </P> <P> A large number of important battles occurred in Tennessee, including the vicious fighting at the Battle of Shiloh, which at the time was the deadliest battle in American history (it was later surpassed by a number of other engagements). Other large battles in Tennessee included Stones River, Chattanooga, Nashville, and Franklin . </P> <P> Tennessee was one of the most divided states in the country at the outset of the war . Before the bombardment of Fort Sumter, Tennessee was actually staunchly pro-Union, though there were still a few secessionist hot beds in the western portion of the state . The situation changed when Fort Sumter was bombarded and Lincoln made the call for 75,000 volunteers to suppress the rebellion . Tennesseans saw this as a threat to their "southern brethren," and the only real pockets of pro-Unionism came from the eastern portion of the state . In fact, Tennessee would furnish more troops for the Union than any other Confederate state, combined . However, over three times that number volunteered for the Confederacy . Interestingly, notable general Nathan Bedford Forrest voted against secession, but later fought for his state when it seceded . </P> <P> Initially, most Tennesseans showed little enthusiasm for breaking away from a nation whose struggles it had shared for so long . In 1860, they had voted by a slim margin for the Constitutional Unionist John Bell, a native son and moderate who continued to search for a way out of the crisis . </P>

Why did the union exert pressure into tennessee
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