Captain Jeremiah O’Brien

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Jeremiah O'Brien

Birthdate: (74)
Death: 1818 (74)
Immediate Family:

Son of Morris (Maurice) O'Brien and Mary O'Brien
Brother of Lieut. William O'Brien; Joseph O'Brien; Dennis O'Brien; John O'Brien and Capt. Gideon O'Brien

Managed by: Daniel Chandler Monroe
Last Updated:

About Captain Jeremiah O’Brien

Captain Jeremiah O’Brien (1744–1818) was a captain in the Massachusetts State Navy. Prior to its existence (or that of the Continental Navy, he commanded the sloop Unity when she captured HMS Margaretta in the Battle of Machias, the first naval battle of the American Revolutionary War.


He was born at Kittery, Maine. O'Brien and his five brothers, Gideon, John, William, Dennis and Joseph, were crewmembers of the sloop Unity when she captured Margaretta on June 12, 1775, at the entrance to the harbor at Machias (a town then in Massachusetts, now in Maine).

Under the command of Jeremiah O’Brien, thirty-one townsmen armed with guns, swords, axes, and pitch forks captured the British armed schooner in an hour-long battle after Margaretta had threatened to bombard the town for interference with the shipment of lumber to British troops in Boston, Massachusetts. This battle is often considered the first time British colors were struck to those of the United States, even though the Continental Navy did not exist at the time. The United States Merchant Marine claims Unity as its member and this incident as their beginning.

O'Brien continued as the captain of Unity, renamed Machias Liberty, for two years, and received the first captain's commission in the Massachusetts State Navy in 1775.

In later years, he had an appointment as the federal customs collector for the port of Machias, a position he held until his death.


Five ships in the United States Navy have been named USS O'Brien for him.
In World War II, the United States liberty ship SS Jeremiah O'Brien was named in his honor.
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Captain Jeremiah O’Brien's Timeline

Age 74