The spring of 1778 brought dramatic changes to the American Theater. The Royal Navy had achieved extensive control of the seas and had soundly beaten units of the Continental fleet in direct confrontation. However, on 12 May 1778 the British commanders in North America learned that France had officially entered the war on the side of the Americans. The British, who had dominated the Atlantic, were forced to loosen their hold on the coastline and make plans to consolidate their strength in New York in order to reinforce their more valuable possessions in the theater. The majority of the Continental Navy fleet had been reduced to river galleys and other small ships able to outrun and evade their much larger British counterparts but also unable to challenge their enemies on the open seas, while Continental Navy ship construction encountered frustrating delays.

In the northern states the port of Boston remained untouchable by the Royal Navy and Army alike. The British lacked the manpower to take the city, which continued to be a principal destination for trade and a staging point for insurgent naval activity. In addition, the British coastal blockades suffered from extreme weather, causing significant damage that could be fully repaired only in Britain. In April, Vice Admiral Viscount Richard Howe sent a large squadron back to England to repair deterioration owing to the heavy demands placed on his ships. To redress the material fatigue of the blockade Vice Admiral Howe recommended construction of a shipyard in New York. The arrival of Continental Army Major General John Sullivan in Rhode Island caused the British to conclude that a major Continental Army operation was underway in Rhode Island. To deprive the American forces a source of resupply, the British made use of their amphibious capabilities and manpower advantage to strike at the stores, livestock, and munitions located on the Elizabeth Islands. The raids destroyed numerous warehouses while taking few casualties. The success of the raids was offset by their collateral political damage, driving the local populace to embrace the American cause.

In April the British had a firm grip on the Mid-Atlantic region. Their control of the entrance of the Chesapeake Bay suffocated trade from Maryland and Virginia. In Delaware and Eastern Maryland loyalist movements evoked a cry for help from the Delaware governor. From their base in Philadelphia, the British struck out at Continental Navy supplies and materiel in the Delaware River. In these amphibious assaults they destroyed more than forty ships, including two stripped-down Continental Navy frigates that had been sunk and refloated, Effingham and Washington. British raids along the coast of Delaware caused concern among Americans when prominent American supporters were kidnapped.

In the South, the British faced a serious threat from the Continental Army forces under Major General Robert Howe. The Georgia State Navy along with Continental reinforcements managed to reduce the Province of East Florida to a single ship for defense in action near Frederica Island in the Altamaha River, where they captured East Florida Sloop Rebecca and HM Armed Sloop Hinchinbrook. In Spanish Louisiana, a Continental Army contingent under command of Captain James Willing had taken refuge in the city of New Orleans after attacking British holdings and capturing prizes in West Florida. From there, Willing moved outside the city and carried out several amphibious raids on British plantations in West Florida, causing a diplomatic standoff between the Spanish and British. The British increased their naval presence around the city and made protests to the Spanish, who rebuffed British attempts to persuade Governor Bernardo de Gálvez to seize and turn over the Americans. Gálvez publicly maintained neutrality, rebuffing British demands as well as enforcing a strict policy against the Americans’ outfitting ships for the purpose of attacking the British.

The Marine Committee, after experiencing shortages of funds, resumed construction of naval vessels at Portsmouth, New Hampshire, and New London, Connecticut, and saw frigate Alliance completed at Salisbury, Massachusetts. The March 1778 captures of Continental Navy frigate Alfred as its consort the frigate Raleigh looked on and of the frigate Virginia within days of its launch called the American frigate captains’ competence into question and induced the Marine Committee to order formal inquiries. In contrast, Captain Abraham Whipple, Continental Navy frigate Providence, engaged and evaded several British warships in a daring escape from Narragansett Bay under the cover of a storm and headed for France. Several other Continental Navy ships returned from France, including frigates Queen of France, Deane, and Raleigh, which carried copies of the Franco-American treaties.

The Franco-American treaties arrived at the Continental Congress on 25 April. Having quickly ratified the treaties, Congress commissioned six vessels to assure that at least one signed copy of the treaties reached the American Commissioners in France. The French alliance gave the American cause a major morale boost in the spring of 1778 by promising a revival of trade when the British were forced to regroup their naval assets to face the French fleet. The major change in North America began on May 12th, 1778 when Vice Admiral Viscount Howe sent out orders to bring the majority of the British warships in North America to the mouth of the Delaware River to aid in the evacuation of Philadelphia as well as to begin the formation of a task force to intercept the French Fleet from Toulon.