The next eventful interval in the life of Fort San Carlos had to do with one of the most popular figures of United States history, Andrew Jackson. In 1814, during the progress of the second war of the United States with England, Jackson was made a major-general and was given command of the Gulf Coast region where he had been operating against the Creek Indians. While arranging a treaty with these conquered savages he was informed by them that they had been approached by English officers, through the connivance of the Spanish commander at Pensacola, with offers of supplies and assistance to fight against the Americans. Two British vessels arrived at Pensacola August 4 and Colonel Edward Nicholls in command was allowed to land troops and to arm some Indians. Late in August seven more British vessels arrived at Pensacola and the mask of Spanish neutrality was thrown aside when Fort San Carlos was turned over to the British, the British being allowed to hoist their ensign thereon, and Colonel Nicholls was entertained by the Spanish governor as his guest. Jackson was at Mobile, Alabama, not very far distant as the crow flies from Pensacola, and when the intelligence of these happenings had been confirmed immediately set about raising a force of Americans. By November he had 2,000 volunteers and early in that month marched from Fort Montgomery (Montgomery, Alabama) upon Pensacola. November 6 he was two miles from that city. To ascertain the Spaniard’s intentions he sent Major Pierre to wait upon the commandant of the city and was rewarded for his pains by having his envoy fired upon. By midnight Jackson had his men in motion against the city, and in the hot engagement which followed the Spanish and British were badly worsted. The British fled down the Bay in their ships, blowing up Fort San Carlos in their retreat and carrying away one of the higher Spanish officers--certainly, on the whole, a not very grateful return for the benefits bestowed upon them by their hosts. The Creek and Seminole Indians who had begun to rally to the English standard were much impressed by this display of force on the part of the Americans and esteeming Jackson a very bad medicine, indeed, wisely decided to return to the prosaic paths of peace. During the Civil War, Fort San Carlos played no conspicuous part. The limelight of fame was thrown on its close neighbor, Fort Pickens, on Santa Rosa Island. This latter post at the outbreak of the war was in charge of Lieutenant Adam J. Slemmer, a Pennsylvanian, who, seeing the conflict impending, concentrated (in Fort Pickens as being the easiest one of them all to defend) the forces in the various forts under his jurisdiction. From January 9 to April 11, 1861, Slemmer was in a state of siege in Fort Pickens and on the latter date was relieved by forces from the North. The point was held by Federal troops throughout the war.