American Civil War: During the Vicksburg campaign, Union forces under Ulysses S. Grant win the Battle of Port Gibson and establish a firm presence on the east side of the Mississippi River.

The Vicksburg campaigns were a series of maneuvers and battles in the Western Theater of the American Civil War directed against Vicksburg, Mississippi, a fortress city that dominated the last Confederate-controlled section of the Mississippi River. The Union Army of the Tennessee under Major General Ulysses S. Grant gained control of the river by capturing this stronghold and defeating Lieutenant General John C. Pemberton's forces stationed there.

Ulysses S. Grant was the 18th president of the United States, serving from 1869 to 1877. In 1865, as commanding general, Grant led the Union Army to victory in the American Civil War.

The Battle of Port Gibson was fought between a Union Army commanded by Major General Ulysses S. Grant and a reinforced Confederate States Army division led by Major General John S. Bowen. Though the outnumbered Confederate soldiers fought stubbornly, they were steadily pressed back during the day by Major General John A. McClernand's troops. Bowen eventually conceded the field by withdrawing north toward Vicksburg, Mississippi. The battle occurred near Port Gibson, Mississippi, during the Vicksburg Campaign of the American Civil War.

The Mississippi River is the primary river of the largest drainage basin in the United States. It is the second-longest river in the United States, behind only the Missouri. From its traditional source of Lake Itasca in northern Minnesota, it flows generally south for 2,340 mi (3,770 km) to the Mississippi River Delta in the Gulf of Mexico. With its many tributaries, the Mississippi's watershed drains all or parts of 32 U.S. states and two Canadian provinces between the Rocky and Appalachian mountains. The river either borders or passes through the states of Minnesota, Wisconsin, Iowa, Illinois, Missouri, Kentucky, Tennessee, Arkansas, Mississippi, and Louisiana. The main stem is entirely within the United States; the total drainage basin is 1,151,000 sq mi (2,980,000 km²), of which only about one percent is in Canada. The Mississippi ranks as the world's tenth-largest river by discharge flow, and the largest in North America.