During the winter months of January, February, and March 1778, British and American naval efforts in the American Theater reflected conditions created by the momentous events of the previous autumn, the capitulation of Lieutenant General John Burgoyne's British army at Saratoga, New York, and the capture of Philadelphia by British forces under General Sir William Howe and Vice Admiral Richard, Lord Howe. Expectation of France's imminent entrance into the war in support of American independence influenced many decisions by naval leaders in America. The British Navy strove to maintain an effective blockade of the American coast, despite the deteriorating condition of their warships, while supporting the British army's footholds in the rebellious territories in the seaports of New York, Newport, and Philadelphia. Needing to get cruising warships to sea, as well as ship­ments to Europe of American produce, particularly tobacco, and to allow ship­ments of munitions, uniforms, and salt into their ports, American revolutionaries struggled to pierce the blockades of the Narragansett Bay, Long Island Sound, Chesapeake Bay, and Charleston S.C., while taking advantage of weaknesses in the blockade, particularly at Boston, the eastern shore of Maryland and Virginia, and the inlets of North Carolina's Outer Banks.

Although Americans had rebuilt the fort at Machias, Maine, Sir George Collier at Halifax reported the province of Nova Scotia in no danger of invasion. Royal Navy ships and provincial armed vessels continued to capture American privateers operating in Nova Scotia's bays and inlets.

An American project to send the French armed ship Flammand, with a few American officers on board authorized to make prizes, from Portsmouth, N.H., to Charleston for a cargo of rice, failed because the French crew, deceived as to their original destination, which they had been told was the French West Indies, refused to sail for Charleston.

The ship Royal Bounty was carrying American prisoners from Halifax to Newport when the prisoners rose, took over the vessel and brought her into Marblehead. British authorities claimed credit for the prisoners on the balance sheet of prisoners exchanged, but Americans denied that the vessel should be con­sidered a cartel, since it was coming from one British-held port and heading for another.

Boston's secure harbor accommodated several ships fitting out, including Continental Navy brig General Gates and Connecticut Navy ship Defence. Continental Navy frigate Boston, Captain Samuel Tucker, set sail from Massachusetts Bay on 17 February, carrying John Adams, appointed to take the place of Silas Deane as one of the American Commissioners in France. The State of Massachusetts ordered brigantine Massachusetts on a cruise off England or the Iberian Peninsula and fitted out several state trading vessels, dispatching Adams and Favorite to France via South Carolina, Gruel, Nantes, and Union to France, and Dolphin to Spain. The British captured Gruel off Halifax and Union before she reached France.

Continental Navy frigates Providence and Warren and ship Columbus fitted out at Providence, R.I., awaiting a good opportunity to sail through the British squadron based in Newport. In a heavy fog on the night of 16 February, Warren slipped past the blockaders in the Narragansett and, after a short cruise, made it to the safety of Boston. But Columbus, attempting to break out on 27 March, ran aground and the British burned her.

British transports prepared to proceed to Boston to take on board the Convention Army that had capitulated at Saratoga the previous October, until the Continental Congress abrogated the agreement to release the British soldiers.

Work continued on the building of Continental Navy frigate Confederacy at Norwich, Connecticut. The state government appointed its own agent to devise a way to get the new Continental Navy frigate Trumbull safely over the bar in the Connecticut River at Saybrook.

British authorities made the decision to issue privateering commissions at New York. They also planned to establish a navy yard at New York City, to alleviate the vexing problems of maintaining Royal Navy vessels on the North American station. Vice Admiral Richard, Lord Howe, noted the depletion of naval stores  and sea­ men's clothing in his fleet. Observing that some of his frigates, long on station, would soon be unfit for service, he recommended more frequent relief of ships assigned to him. Considering the aid to the Americans in ships of force expected from "foreign Powers," he suggested that the frigates be replaced with ships of the line. Howe voiced doubts that, with the forces at his command, he would be able to detach ships occasionally for the defense of Newfoundland or  for convoying trade from the West Indies. During the unusually cold winter of 1777-78, the infamous winter of Valley Forge, ice clogged the Delaware River so that the British shipping at Philadelphia was, for the most part, confined to the wharves until 8 March. The Americans con­ceived of several methods of destroying that shipping. The satirical poem The Battle of the Kegs immortalized David Bushnell's unsuccessful attempt to float kegs of gun­ powder fitted with detonating devises through the ice-choked river against British vessels along the wharves. Major Francois Louis Teissedre de Fleury, of the Continental Army, proposed a rocket-powered fire boat; he also proposed sending men over the ice with shirts impregnated with sulfur to set fire to the ships. General George Washington ordered the erection of a battery across the river from the wharves, in an attempt to destroy the shipping with heated shot.

The Americans employed armed boats to stop market boats from supplying Philadelphia, and the State of Pennsylvania commissioned its navy's barges as privateers to capture transports attempting to reach the city. A few such transports became caught in the ice and were captured by American forces. In January, the crews of two Pennsylvania Navy armed boats defected, with the boats, to the British. Under persistent pressure from George Washington, the state of Pennsylvania eventually agreed to sink its galleys in creeks to prevent their capture by the enemy. In mid-February, a Continental Army detachment under Brigadier General Anthony Wayne requested Continental Navy Captain John Barry's assistance with a foraging expedition on the New Jersey shore. Under Barry's command, a force, act­ing in armed boats along the Delaware River shore, burned hay needed by the British in Philadelphia to feed their horses. The raid acted as a diversion, allowing Wayne to make off with a large herd of cattle for the Continental Army.

On 7 March, Barry's command, consisting of two Continental Navy barges and three Pennsylvania Navy armed boats, captured two British transports, laden with hay for the British army, and their escort, the armed schooner Akrt, in the service of the British army's engineering department. Barry ordered the large  assortment of engineering tools on board unloaded. To prevent their recapture Barry had the transports burned, but he attempted to escape in Akrt, renamed Continental Navy schooner Wasp. Unable to evade the superior force of the four British warships in pursuit, Barry ran the schooner on shore.

Continental Navy Captain Isaiah Robinson and Captain Nathaniel Galt of the Pennsylvania State Navy sailed to Philadelphia under a flag of truce with provisions for American prisoners held there, but the British placed the two men under arrest as spies.

Dissatisfied with Continental Navy Commander in Chief Esek Hopkins's per­formance and failure to obey orders, Congress dismissed him from service on 2 January.

The Continental Navy Board of the Middle Department reprimanded Captain John Barry for disrespect to Stephen Hopkinson, a member of the board. The two had exchanged heated words when Hopkinson interfered with Barry's efforts to carry out the board's orders to sink the frigate Effingham.

The Royal Navy maintained an effective blockade of the Virginia Capes, cap­turing many vessels attempting to leave or enter the Chesapeake, including several heavily armed merchantmen from France and the Maryland state trading vessel Lydia. The Maryland Navy offered the ship Defence for sale. On 31 March, Continental Navy frigate Virginia, Captain James Nicholson, broke her rudder on the Middle Ground shoal and was captured as she was making the last of several foiled attempts to sail past the blockade. Maryland, Virginia, and North Carolina cooperated in protecting navigation in the Chesapeake Bay, with their navies' gal­leys transporting goods and interfering with British operations in shallow waters. Maryland struggled to man its armed vessels, and Virginia built two galleys on the eastern shore to protect shipping along the seaboard.

Unable to enter the Chesapeake, Denis-Nicolas Cottineau de Kerloguen took his heavily armed merchantman Ferdinand into Cape Lookout Bay, North Carolina, where he established a shore battery to protect his ship as he discharged its cargo. Cottineau would later see service with the Continental Navy, along with his fellow Frenchman, Pierre Landais, who had come to America as master of the merchant­ man Flammand.

On 15 January 1778 an extensive fire in Charleston, S.C., destroyed several hundred houses, causing damages valued by one estimate at half a million pounds. Many Charlestonians believed the fire to be the work of the British men-of-war's boat crews who nightly came ashore from the blockading squadron. The ships of this squadron patrolled the coast from South Carolina to East Florida, but most remained off Charleston, the main trading port of the rebellious South, where they took many merchant vessels as prizes.

Attempting to protect their trade, the South Carolina government fitted out a squadron of armed vessels, consisting of the ship General Moultrie, the brigantine Notre Dame, and the brigs Polly and Fair American. Difficulties manning and the need to train new recruits delayed the squadron's sailing until 12 February. By then the Continental Navy frigate Randolph, which was also fitting out at Charleston, had augmented the squadron. The frigate's commander, Captain  Nicholas  Biddle, wishing to test his new ship against the British, consented to delay sailing until South Carolina's small fleet was ready to put to sea.

Randolph, Biddle, and all but three of the crew never returned from this cruise. The fleet safely passed the blockading British squadron and sailed for the West Indies. There it encountered H.M.S. Yarmouth, of sixty-four guns. The crew of the American frigate fought valiantly against the British ship of the line, but the heavy fire of the latter resulted in Randolph's blowing up. The other ships of the squadron escaped to Charleston.

The government of South Carolina may have intended its fleet merely to drive the British warships from the vicinity of Charleston, but British intelligence thought it was destined either to attack St. Augustine or to convoy a large number of American and French merchantmen past the British warships waiting offshore.

Alexander Gillon accepted appointment as head of the South Carolina Navy on condition that he be allowed to journey to France to obtain three frigates for the navy he was to lead.

Georgia's naval force consisted of several galleys for defense and for the appre­hension of smugglers who supplied the British at St. Augustine. Unable to man the galleys adequately with volunteers, the state's executive council sought cooperation of the Continental Army to allow soldiers to serve in them.

Anticipating an attack on East Florida, the British stationed Galatea, Hinchinbrook, and East Florida province armed sloop Rebecca permanently off the coast at Frederica, Ga., to defend the inland navigation to the St. Mary's River, which the British fleet used for fresh water.

Bermuda was a valuable source of salt for the Continental forces, required for curing beef and pork, while Bermudans, unable to raise sufficient foodstuffs themselves, surreptitiously engaged in proscribed trade with the mainland. When Virginia Loyalist Bridger Goodrich, holding a privateering commission from the governor of Bermuda, seized Bermudan vessels engaged in that illegal commerce, he found himself and his ship threatened with violence by the enraged islanders.

On 10 January, a detachment of Continental Army troops under Captain James Willing set out from Pittsburgh in the Continental Army armed boat Rattle Trap on an expedition down the Ohio River to the Mississippi. At Natchez, Willing had the residents sign a capitulation and declaration of neutrality. At the British settlement of Manchac, Willing's party captured the ship Rebecca, of sixteen guns. The American force took several other trading vessels, seized slaves, and brought their booty into New Orleans. Louisiana's Governor Bernardo de Galvez issued a proclamation of neutrality, offered protection to British subjects fleeing the invaders, and refused British demands to turn out the Americans and return the seized British property. He allowed the Americans to sell the property to Spanish citizens, who obtained the goods and slaves at bargain prices, while he secretly transferred to Oliver Pollock, the resident agent of the Continental Congress, supplies that had been sent from Spain. The governor and council of British West Florida, in Pensacola, created a provincial corps and sought the assistance of native allies in expelling Willing's force. Meanwhile, the British Navy dispatched H.M. sloops Sylph and Hound into the Mississippi and sent men to reinforce H.M. sloop West Florida, on Lake Pontchartrain.