The Battle of Thompson's Hill

Port Gibson, Miss., May 1, 1863. 13th Army Corps, and 3rd Division of the 17th Corps. Port Gibson is a small village a few miles southeast of Grand Gulf. The engagement here was the beginning of Grant's active campaign against Vicksburg. The 13th corps, Maj.-Gen. John A. McClernand commanding, left Bruinsburg about 4 p.m. on April 30, with Carr's division in advance, followed in order by Osterhaus, Hovey and A.J. Smith, and moved toward Port Gibson.

That same afternoon Confederate Gen. J.S. Brown, commanding the garrison at Grand Gulf, learning that Grant had crossed the Mississippi at Bruinsburg, sent a portion of Green's brigade to guard the approaches to Port Gibson, and at the same time telegraphed to Pemberton that the Union army was on the east side of the river. Pemberton became alarmed and ordered Tracy's and Baldwin's brigades, of Stevenson's division, to reinforce Grand Gulf. About an hour after midnight Carr came in contact with Green's brigade, posted across the road about 3 miles west of Port Gibson. A slight skirmish ensued, which resulted in the withdrawal of the Confederates, and the Union troops rested on their arms until daylight.

At this point the road from Bruinsburg to Port Gibson divides. When daylight came Green's brigade was drawn up across the southern and Tracy's across the northern road. McClernand ordered Osterhaus forward on the right hand road to attack Tracy, and Carr on the left hand road against Green. At 5:30 Osterhaus was engaged, and met with such a stubborn resistance that he was unable to make any further advance until late in the afternoon. Carr formed his line with Benton's brigade on the right of the road and Stone's on the left, and moved forward against Green, who was strongly posted on a ridge. In the advance the two brigades became separated, leaving a gap in the line, which was closed by Hovey's division about 7 o'clock, when a determined assault was made, the ridge was carried, 2 cannons, 3 caissons and about 400 prisoners being captured. Green fell back toward Port Gibson, closely pressed by Hovey and Carr. Near the village they encountered Baldwin's brigade coming up to Green's support, and a severe contest of an hour and a half followed.

Bowen in the meantime had ordered Cockrell to send three regiments to Port Gibson. These arrived about noon and two regiments were sent to the assistance of Baldwin and one to Tracy. Green's brigade was withdrawn from the southern road and sent to Tracy also. Bowen himself arrived on the field about this time and led two of Cockrell's regiments in a desperate effort to turn the Union right, but Burbridge's brigade, of A.J. Smith's division, came up at this juncture and was thrown forward to meet the movement.

At the same time Hovey brought four batteries into position to enfilade Bowen's line, forcing him to retire in some confusion. Not knowing the strength of the enemy opposed to him, McClernand sent back for reinforcements. McPherson sent Stevenson's brigade to the support of Carr and Hovey and J.E. Smith's to Osterhaus. About 5 p.m. the latter got into position to strike the enemy on the right flank, while Osterhaus renewed the attack in front. Tracy had been killed early in the engagement and Green, who was now in command, hurriedly retreated in the direction of Grand Gulf, burning the bridge over Bayou Pierre behind him, thus checking pursuit. Before Stevenson's brigade reached the scene of action Baldwin was driven from his position, falling back through Port Gibson and destroying the bridge over the south fork of Bayou Pierre.

Sunset found the Federals in possession of the field, with a loss of 131 killed, 719 wounded and 25 missing. Bowen's entire force numbered about 8,500 men, but he was able to hold the whole 13th corps in check the greater part of the day, owing chiefly to his advantageous positions. He reported his loss as being 68 killed, 380 wounded and 384 missing. This action is also known as "Anderson's Hill," "Thompson's Hill," and "Magnolia Hills."