Encouraged by the success of his army in defeating Union forces at Chancellorsville, and convinced that the stifling heat of the approaching summer would force Ulysses S. Grant to give up his quest to capture Vicksburg in the west, in mid-May of 1863 General Robert E. Lee presented a new idea to President Jefferson Davis and the Confederate government. He would invade the north.
Confederate Secretary of War James Seddon proposed sending General James Longstreet, one of Lee’s most trusted commanders, into Mississippi to reinforce General John Pemberton at Vicksburg. Lee, however, disagreed. Longstreet was 1,000 miles from Vicksburg and the southern railroads were mangled, making it very difficult to move a large number of men and needed materiel to the west. If Pemberton could hold out long enough, Lee theorized, Grant would give up on Vicksburg.