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May, 1862, Gen. Fitz-John Porter was sent by General MeClellan with a considerable force to keep the way open for McDowell's army to join him, which he persistently demanded, in order to venture on a battle for Richmond. Porter had some sharp skirmishes near Hanover Courthouse, and cut all railway connections with Richmond, excepting that from Fredericksburg.
What is the Battle of Seven Pines?