At an early hour on April 28, 1863, Colonel James Keigwin ordered forward a combat patrol to ascertain if Lt. Colonel Isaac F. Harrison's Confederate cavalrymen were in position behind Choctaw Bayou, and thus still a menace to the bridges over Phelps and Clark Bayous. Harrison's troopers were found in a strong position behind Choctaw Bayou with their right flank resting on Lake Bruin. The Confederates also had a battery of four guns emplaced on a point of land jutting out into the lake. Keigwin brought up his infantry and placed two 10-pdr Rodmans in position. The Union cannon roared into action and sent the Confederate cavalrymen scurrying to the rear. Federal skirmishers quickly advanced across an open field, and moved into position along the streambank, where they issued a punishing fire against the Confederate artillerymen. After an hour, the Southerners limbered up their guns and withdrew toward St. Joseph. Satisfied that he had removed the threat to the bridges and having no orders to bridge Choctaw Bayou, Keigwin did not pursue. The small Federal force marched to Winter Quarters and bivouacked for the night.
Fight at Choctaw Bayou, April 28, 1863