We got up this morning and found a heavy frost but the day came off clear and warm. The troops were crossing the river all night. I heard that the Pontoon Bridge broke again some time in the after part of the night which caused a delay of 5 or 6 hours. We had orders to be ready to march at 2 PM we crossed the river marched out about a mile and went into camp for the night. I read 6 Chapt. in Testament.
Early in the War, Union commanders realized that retaking the Mississippi River would be important in isolating Texas and the West from the core of the Confederacy. Gen. Winfield Scott‘s Anaconda Plan combined the blockade of Southern ports with control of the Mississippi, not only to impede Rebel troop movements, but also to isolate the Southern economy.
With control of the lower Tennessee River after Shiloh, Gen. Grant moved on to the Vicksburg Campaign. In November, 1862, Maj. Gen. Sherman moved with the XV Corps from Memphis to join Grant’s forces at Holly Springs and Oxford, for a thrust south through middle Mississippi. Through December and into January, 1863, Confederate and Union forces played cat and mouse across interior Mississippi and into West Tennessee, while Sherman probed south along the Mississippi River to Vicksburg, which commanded the River from high bluffs on the east bank. Through the winter, Union forces tired digging canals to bypass the stronghold, an exercise in flooded frustration. When that didn’t work, Grant proposed to march his troops through the bayous on the river’s west bank and have Rear Adm. David Dixon Porter run his boats past the Confederate guns.
The big risk in running the gauntlet at Vicksburg was it meant severing their own supply lines and living off the land. It was a huge risk, and it worked. While Sherman made a feint north of the city (Snyder’s Bluff, 29 April – 1 May), Grant crossed the river several miles to the south and together with Gen. James McPherson they set off to take the state capital at Jackson. Which they did, on 14 May, chasing out Confederate Gen. Joeseph E. Johnston and proceeding to burn the place. Returning to Vicksburg, Grant failed to break through defensive lines and had to settle into a long siege. Sherman was shifted to the IX Crops, with orders to prevent Confederate forces from opening a second front from the east. Vicksburg fell on 4 July 1863, the day after the Union victory at the Battle of Gettysburg.
Vicksburg is widely considered Grant’s greatest victory. Sherman clearly remembered the lessons, of the reward of quickly moving on the enemy at the risk of abandoning your own supply train, and of the impact on morale of systematically destroying both the actual means and symbols of the Southern war effort. He would get a chance to apply those lessons, when Gen. Grant was assigned next to Chattanooga. Which is also where our hero caught up to Gen. Sherman a year later.