By the end of March 1863, Major General Ulysses S. Grant was at a crossroads in his military career. His bold attempts in the late fall 1862 and winter of 1862/63 had all come up fall short of his objective: get his army on high ground north and east of Vicksburg and capture the last major obstacle on the Mississippi River.Grant had been stymied by the difficult region’s swampy bayous as well as Confederate resistance at key locations that thwarted his advances and prolonged his army’s miserable dispositions in the sickly camps of Louisiana bottomland. Confederate Lieutenant General John C. Pemberton had performed well using his interior rail lines and intelligence networks to place blocking forces or obstructions that delayed or derailed Grant’s movements.Realizing his career was on the line, Grant chose the riskiest operation he could have concocted. In a joint military operation, Grant marched two of his army corps down the roads and along the bayous of Louisiana, repairing them as they progressed, while Acting Rear Admiral David Dixon Porter led his ironclad gunboats with transports past the Confederate heavy artillery defending Vicksburg’s riverfront. It was Grant’s hope to get enough boats below the city to enable a crossing of the Mississippi River, a forced march into the state, and arriving at Vicksburg’s doorsteps from the east–west approach. In doing this, Grant would severe his main line of logistics and supply, something his subordinate officers thought was a disastrous mistake. Grant would take the risk in a zero-sum game: he would capture Vicksburg or destroy himself and his army doing so.This Casemate Illustrated examines the movements of the Union and Confederate armies from March 1863 through July 1863, the joint-operational cooperation between the U.S. Army and U.S. Navy, the delayed and indecisive Confederate operations to stop the Federal initiative, and how the individual soldiers conducted the one of the greatest campaigns in American military history: to control the “The Father of Waters”—the Mississippi River.