John G. Nicolay, The Outbreak of Rebellion

The spell was finally broken on December 31st, when Mr. Buchanan accepted Floyd's resignation, which the latter reluctantly tendered on the 29th; he also sent the commissioners their definite answer, namely: that, whatever might have been his first inclination, the Governor of South Carolina had, since Anderson's movement, forcibly seized Fort Moultrie, Castle Pinckney, and the Charleston Arsenal, Custom-House, and Post-Office, and covered them with the Palmetto flag; that under such circumstances he could not and would not withdraw the Federal troops from Sumter. This ended the rebel mission. They departed abruptly for home, leaving behind them an insolent rejoinder to the President's letter, charging him with tacit consent to the scheme of peaceable secession.

Governor Pickens (newly chosen by the Legislature, December 14th) was perhaps the most daring revolutionist in South Carolina, and as commander-in-chief of the State forces he at once assumed and exercised dictatorial powers. Within three or four days after his seizure of the forts he ordered the selection of suitable points on the islands forming the bay, and the commencement of batteries to command the ship-channels against reinforcements. It was the beginning of the long and eventful siege of Sumter. Moultrie was soon restored to its offensive powers; Castle Pinckney passed into his hands undamaged; with a working force of volunteers impelled by fanatical zeal, supplemented by the more efficient labor of large gangs of slaves freely furnished from the city and plantations of the neighborhood, battery after battery rose around Anderson's stronghold, unmolested and unchecked for three long months, until, in an encompassing ring of fire, and under the sheer overweight of metal and numbers, the proud flag of Sumter went down in temporary humiliation.