On June 18, the First Missouri Brigade was engaged in a small action in the vicinity of the Lattimer House. After this action, the brigade then fell back to Kennesaw Mountain. On June 27, the First Missouri Brigade, commanded by Brigadier General Francis M. Cockrell, defended a portion of the Confederate line at a point known as Pigeon Hill. Union skirmishers hit the Confederate line at around 8:00 a.m., followed by more Union troops. The Confederate skirmish line held for some point, but Union pressure drove in the left flank of the line. The right flank of the skirmish line was later ordered to fall back, suffering heavy losses in the retreat. Union troops then charged Cockrell's main line, but were replused. Flournoy is reported to have fought with the Confederate skirmish line. Despite having won the battle, Confederate General Joseph E. Johnston ordered a retreat from Kennesaw Mountain. On July 3 and 4, the 2nd and 6th Missouri Infantry saw light action near Smyrna, Georgia; several men of the regiment were killed in the actions. The First Missouri Brigade was present at the Battle of Peachtree Creek on July 20. While Major General Samuel Gibbs French, commanding the division the 2nd and 6th Missouri Infantry was in, reported that only skirmishers of his division were engaged, a lieutenant in the 3rd and 5th Missouri Infantry Regiment (Consolidated) wrote that the First Missouri Brigade was subject to hot and heavy fire for five hours during the battle.