The first Naval Battle occurred before their was a United States Navy. After the battles of Lexington and Concord on 19 April 1775, American militia laid siege to the city of Boston. The British, under General Thomas Gage was forced to import supplies by sea as land access was cut off. A Loyalist merchant, Ichabod Jones, made a deal with Gage to sail to Machias, ME (then part of Massachusetts) and bring back a load of lumber to Gage.
Jones; ships Polly and Unity left Boston, for Machias, accompanied by the HMS Margaretta for security. Upon arrival in Machia, Jones attempted to obtain lumber from the local merchants. The citizens of Machias did not want to do business with the loyalist so, in an attempt to cause alarm asked the Margaretta to close in on shore. After another attempt to do business the local militia boarded Jones' ships, Polly and Unity, and demanded the surrender of the Margeretta. The Margeretta fled. The Unity was equipped for battle, and along with another ship, the Falmouth Packet, overtook the fleeing Margeretta. After an exchange of shots the Margeratta, after their captain was down, surrendered to the militia men from Machias. The Unity and Falmouth Packet were under command of Jeremiah O'Brien who served with distinction during the Revolutionary War and had five Naval Vessels named after him.
The World War II merchant marine vessel named Jeremiah O'Brien (Liberty ship) is a tourist attraction docked near Pier 39 in San Francisco. It was bought into steaming condition by a team of ex merchant marines and other civilian volunteers and sailed to Normandy, France and back for one of the D-Day celebrations.