Col. J. J. Dickison, Confederate Military History, a library of Confederate States Military History: Volume 11.2, Florida
Clement Anselm Evans, Ed.

On April 1st a second and more formidable Federal expedition was ordered to the Gulf coast under Colonel Harvey Brown, who was given command of Florida by the Federal government and ordered to make Fort Jefferson his main depot and base of operations. He sailed on the ship Atlantic, followed by the Illinois, carrying stores, and the ships Sabine, St. Louis and Crusader were also in the expedition, as well as the Powhatan under Lieut. David D. Porter, all indicating the intention of the United States to make a formidable effort to retain armed possession of its strongholds at Key West, Dry Tortugas and Santa Rosa island. The forces with Colonel Brown landed April 18th, and troops continued to arrive, it being the intention to put 3,000 men on the island.

Meanwhile the government of the Confederate States was not idle. Provisional forces were called out for the defense of Pensacola harbor: 1,000 from Georgia, 1,000 from Alabama, 1,000 from Louisiana, 1,500 from Mississippi, and 500 from Florida; in all 5,000 infantry. General Bragg had an aggregate present on the last of March of a little over 1,000 Confederate State troops, and reinforcements soon began to arrive, so that he had 5,000 on the 14th of April, and advices of 2,000 more coming. On the 20th, the Federal expedition having arrived, affairs grew more warlike along the lines of works frowning across the bay. All intercourse with the Federals was prohibited by General Bragg, and martial law was declared at the Confederate position. But for some time there were no active operations, and late in May some of the troops at Pensacola were called to Virginia.

At other points the State of Florida had made warlike preparations for defense against hostile invasion, although it was realized that it was impossible to fortify the whole coast. From Pensacola to St. Augustine, 1,400 miles