<Li> Brig. Gen . John A. McClernand </Li> <Li> Brig. Gen . Charles F. Smith </Li> <Li> Brig. Gen . Lew Wallace </Li> <P> Grant's Union Army of the Tennessee of the District of Cairo consisted of three divisions, commanded by Brig . Gens . McClernand, C.F. Smith, and Lew Wallace . (At the start of the attack on Fort Donelson, Wallace was a brigade commander in reserve at Fort Henry, but was summoned on February 14 and charged with assembling a new division that included reinforcements arriving by steamship, including Charles Cruft's brigade on loan from Buell .) Two regiments of cavalry and eight batteries of artillery supported the infantry divisions . Altogether, the Union forces numbered nearly 25,000 men, although at the start of the battle, only 15,000 were available . </P>

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