As soon as it was known that an armament was fitting out at New York many suspected that the southern States were to be assailed, and such was the unhappy posture of American affairs at that time, that no sanguine expectations of a successful resistance could be reasonably entertained. The magazines of the Union were everywhere almost empty, and Congress had neither money nor credit to replenish them. The army at Morristown, under the immediate orders of Washington, was threatened, as we have seen, with destruction by want of provisions, and consequently could neither act with vigor in the North, nor send reinforcements to the South.
General Lincoln, though aware of his danger,—was not in a condition to meet it. On raising the siege of Savannah he had sent the troops of Virginia to Augusta; those of South Carolina were stationed partly at Sheldoa, opposite Port Royal, between thirty and forty miles north from Savannah, and partly at Fort Moultrie, which had been allowed to fall into decay; those of North Carolina were with General Lincoln at Charleston. All these detachments formed but a feeble force, and to increase it was not easy, for the Colonial paper money was in a state of great depreciation; the militia, worn out by a harassing service, were reluctant again to repair to the standards of their country, and the brave defense of Savannah had inspired the people of the southern provinces with intimidating notions of British valor. The patriotism of many of the Colonists had evaporated; they contemplated nothing but the hardships and dangers of the contest and recoiled from the protracted struggle.
In these discouraging circumstances Congress recommended the people of South Carolina to arm their slaves, a measure to which they were generally averse; although, had they been willing to comply with the recommendation, arms could not have been procured. Washington had, as we have already seen, ordered the Continental troops of North Carolina and Virginia to march to Charleston, and four American frigates, two French ships of war; the one mounting twenty-six and the other eighteen guns, with the marine force of South Carolina under Commodore Whipple, were directed to cooperate in the defense of the town. No more aid could be expected; yet, under these unpromising circumstances, a full house of assembly resolved to defend Charleston to the last extremity.
Although Clinton had embarked at New York on the 26th of December, 1779, yet, as his voyage had been stormy and tedious, and as some time had been necessarily spent at Savannah, it was the 11th of February, 1780, before he landed on John's Island, thirty miles south from Charleston. Had he even then marched rapidly upon the town he would probably have entered it without much opposition, but mindful of his repulse in 1776 his progress was marked by a wary circumspection. He proceeded by the islands of St. John and St. James, while part of his fleet advanced to blockade the harbor. He sent for a reinforcement from New York, ordered General Prevost to join him with 1,100 men from Savannah, and neglected nothing that could insure success.
General Lincoln was indefatigable in improving the time which the slow progress of the royal army afforded him. Six hundred slaves were employed in constructing or repairing the fortifications of the town; vigorous though not very successful measures were taken to bring the militia into the field; and all the small detachments of regular troops were assembled in the capital. The works which had been begun on Charleston Neck when General Prevost threatened the place were resumed. A chain of redoubts, lines, and batteries was formed between the Cooper and Ashley rivers. In front of each flank the works were covered by swamps extending from the rivers; those opposite swamps were connected by a canal; between the canal and the works were two strong rows of abattis, and a ditch double picketed, with deep holes at short distances, to break the columns in case of an assault. Toward the water, works were thrown up at every place where a landing was practicable. The vessels intended to defend the bar of the harbor having been found insufficient for that purpose, their guns were taken out and planted on the ramparts, and the seamen were stationed at the batteries. One of the ships, which was not dismantled, was placed in the Cooper river to assist the batteries, and several vessels were sunk at the mouth of the channel to prevent the entrance of the royal fleet. Lincoln intended that the town should be defended until such reinforcements would arrive from the North as, together with the militia of the State, would compel Clinton to raise the siege. As the regular troops in the town did not exceed 1,400, a council of war found that the garrison was too weak to spare detachments to obstruct the progress of the royal army. Only a small party of cavalry and some light troops were ordered to hover on its left flank and observe its motions.
While these preparations for defense were going on in Charleston the British army was cautiously but steadily advancing toward the town. As he proceeded Clinton erected forts and formed magazines at proper stations, and was careful to secure his communications with those forts and with the sea. All the horses of the British army had perished in the tedious and stormy voyage from New York to Savannah, but on landing in South Carolina Clinton procured others to mount his dragoons, whom he formed into a light corps, under the command of Lieutenant-Colonel Tarleton. That officer was extremely active in covering the left wing of the army and in dispersing the militia. In one of his excursions he fell in with Lieut.-Col. William Washington, who commanded the remnant of Baylor's regiment, and who beat him back with loss.
On the 20th of March (1780) the British fleet, under Admiral Arbuthnot, consisting of 1 ship of 50 guns, 2 of 44 each, 4 of 32 each, and an armed vessel, passed the bar in front of Rebellion Road, and anchored in Five Fathom Hole.
It being now thought impossible to prevent the fleet from passing Fort Moultrie, and taking such stations in Cooper river as would enable them to rake the batteries on shore, and to close that communication between the town and country, the plan of defense was once more changed, and the armed vessels were carried into the mouth of Cooper river, and sunk in a line from the town to Shute's Folly.
This was the critical moment for evacuating the town. The loss of the harbor rendered the defense of the place, if not desperate, so improbable, that the hope to maintain it could not have been rationally entertained by a person who was not deceived by the expectation of aids much more considerable than were actually received.
When this state of things was communicated to Washington by Lieutenant-Colonel Laurens he said in reply: "The impracticability of defending the bar, I fear, amounts to the loss of the town and garrison. At this distance it is impossible to judge for you. I have the greatest confidence in General Lincoln's prudence, but it really appears to me that the propriety of attempting to defend the town depended on the probability of defending the bar, and that when this ceased, the attempt ought to have been relinquished. In this, however, I suspend a definitive judgment, and wish you to consider what I say as confidential." Unfortunately this letter did not arrive in time to influence the conduct of the besieged.