How did Nathan Bedford Forrest's raids affect Ulysses S. Grant's Vicksburg Campaign?

Nathan Bedford Forrest’s cavalry raids were significantly detrimental to Union General Ulysses S. Grant’s Vicksburg Campaign. By targeting Union supply lines, communication networks, depots, and garrisons throughout the Western theater, Forrest disrupted the logistical support necessary for the Union effort.1

Some contemporary observers and historians have argued that these tactical operations were effective enough to delay the fall of Vicksburg by several months. While Grant eventually succeeded in his campaign by moving his army to the west bank of the Mississippi and crossing south of the city to isolate the Confederate garrison, Forrest’s ability to conduct semi-independent, aggressive raids served as a persistent obstacle to the Union's strategic objectives in the region.12