. When Banks departed New Orleans, he planned to capture Taylor's army in its entirety. On April 9, two
divisions from the XIX Corps crossed Berwick Bay from Brashear City (present day
Morgan City, Louisiana) to the west side at Berwick. On April 11, Banks began his advance in earnest. Taylor was well aware of Banks' advance because of successful scouting by his
cavalry under Brig. Gen.
Thomas Green. Green shadowed Banks' army and reported back to Taylor every detail of the maneuvers of the Union army. On April 12, Banks sent a third division, under
Brig. Gen. Cuvier Grover, up the
Atchafalaya River to land in the rear of Franklin, intending to intercept a Confederate retreat from Fort Bisland or turn the enemy's position. General Taylor sent some of Green's cavalry to the front to ascertain the enemy's strength and slow his advance. He also sent troops under Brig. Gen.
Alfred Mouton to impede the advance of Grover's division. Late in the day, Union troops of Brig. Gen.
William H. Emory's division arrived and formed a battle line outside the Fort Bisland's defenses. An artillery barrage ensued from both sides until dark when the Federal troops fell back to camp for the night. About 9:00 a.m. on April 13, Union forces again advanced on Fort Bisland. Banks had three brigades under in position south of the
Bayou Teche. The brigades were deployed with
Godfrey Weitzel on the left,
Halbert E. Paine on the right (anchored on Bayou Teche) with Timothy Ingraham in support. Opposing the Union forces south of the Teche was the Texas cavalry brigade commanded by Brig. Gen.
Henry Hopkins Sibley. North of Bayou Teche was the Union brigade of
Oliver P. Gooding who faced off against Mouton's Confederate brigade. Combat did not begin until after 11:00 a.m. and continued until dusk. In addition to Confederate forces in the earthworks, the gunboat
Diana, which had been captured and was now in Confederate hands, shelled the Union troops. U.S. gunboats joined the fray in late afternoon. By early evening, fire had halted. Later that night, Taylor learned that the Union division that went up the Atchafalaya and landed in his rear was now in a position to cut off a Confederate retreat. Taylor began evacuating supplies, men, and weapons, leaving a small force to slow any enemy movement. The next morning, Banks and his men found the fort abandoned. ==Aftermath==