1840 for Army engineer Colonel William McRee. Early use The first troops stationed at Fort McRee, the men of I Company, 3rd Artillery, arrived on 2 May 1842. These men were joined by E Company, 7th Infantry in July. From this time until October 1845, when much of the artillery unit was ordered to Louisiana, the fort was manned at various levels. After the Mexican–American War was finished in 1848, barracks were built near Fort Barrancas on the mainland. Once these were completed, Fort McRee was manned only during drills, maneuvers and target practice. The strength of the entire US Army on 1 December 1853 was reported at 10,417, so commanders had to be effective in use of troops. The other two Pensacola area forts were manned in a similar way until the outbreak of the Civil War. Civil War action With less than 50 men to occupy all three fortifications in Pensacola, First Lieutenant Adam J. Slemmer (the senior Army officer present) decided to concentrate his small force in a more defensible location. January 8, 1861 the Union soldiers at Fort Barrancas fired upon the Florida Militia effectively firing the first shots of the war. Over 9 and 10 January 1861, his garrison spiked the guns of Barrancas and McRee then moved across the bay to Fort Pickens. The move was a timely one as on 12 January, Florida and Alabama militia arrived and took control of the evacuated fortifications. Over the next several months, both sides built new cannon batteries and brought in more personnel. The opposing forces engaged in cannon duels many times but with little effect. Near the end of the year, manning stood at about 7,000 men on the Confederate side opposed by 2,000 Union soldiers around Fort Pickens. On 9 October 1861 the commander of Confederate forces in Pensacola, General Braxton Bragg, ordered an assault on Fort Pickens that was ultimately unsuccessful. Colonel Harvey Brown, the commander of Union forces, felt this attack required an answer and planned an attack of his own. Fort McRee, the closest fortification to Fort Pickens and a road block to any attempted assault on Pensacola, was to be the primary target. Starting on the morning of 22 November 1861, Fort McRee was bombarded heavily by Union forces at Fort Pickens, and by two ships, Niagara and Richmond. Initially returning strong fire, the Confederates were able to hold their