Truman Seymour underestimated the Confederate forces at Olustee

Another fact is that Truman Seymour underestimated the Confederate forces at Olustee. Seymour led his 5,500 troops in the direction of Lake City, following the Florida, Atlantic, and Gulf Central Railroad. The Union forces approached General Finegan's 5,000 Confederates entrenched near Olustee Station around 2:30 p.m. on February 20. Seymour made the mistake of presuming he was facing Florida militia groups he had previously easily routed and committed his troops piecemeal to the conflict. During the afternoon, Finegan and Seymour each reinforced their engaged battalions, and the battle took place in open pine forests. The Union forces launched an offensive but were defeated with ferocious barrages of rifle and cannon fire.

The battle continued all afternoon until the Union line crumbled and began to retreat when Finegan sacrificed the rest of his reserves. Finegan did not take advantage of the retreat, allowing the majority of the retreating Union men to reach Jacksonville. The Confederates did make one more attempt to engage Seymour's forces just before dusk, but they were repulsed by parts of the 54th Massachusetts Volunteer Infantry Regiment and the 35th United States Colored Troops, both of which were made up of Black soldiers.