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 the British armed schooner HMS Margaretta in the Battle of Machias, the first naval battle of the American Revolutionary War.
Jeremiah was the eldest son of Morris and Mary O'Brien. He was born at Kittery, Maine in 1744. His family moved to Scarborough, Maine and settled in Machias, Maine in the 1760s to engage in lumbering. Maine was a part of Massachusetts at the time.
Reports of the battles of Lexington and Concord reached Machias in early May 1775. Benjamin Foster rallied Machias residents at Job Burnham's tavern and erected a liberty pole. Machias merchant captain Ichabod Jones sailed his ships Unity and Polly to Boston with a cargo of lumber and purchased food for sale in Machias. British troops encouraged Jones to deliver another cargo of lumber for construction of their barracks in Boston. Admiral Samuel Graves ordered HMS Margaretta, under the command of James Moore, to accompany Jones' ships to discourage interference from Machias rebels. When the ships reached Machias on 2 June 1775, James Moore ordered the liberty pole removed; and Machias townspeople refused to load the lumber. Foster plotted to capture the British officers when they attended church on 11 June, but the British avoided capture and retreated downriver aboard Margaretta. On 12 June Foster pursued Margaretta aboard the packet boat Falmouth. After Falmouth ran aground, O'Brien and his five brothers, Gideon, John, William, Dennis and Joseph, seized the Unity.
Under the command of Jeremiah O’Brien, thirty-one townsmen sailed aboard Unity armed with guns, swords, axes, and pitch forks and captured Margaretta in an hour-long battle after Margaretta had threatened to bombard the town. John O'Brien jumped aboard Margaretta as the two ships closed, but was forced to jump overboard by the British crew. After rescuing John, Unity again closed Margaretta until their rigging became entangled. Unity was bombarded by grenades from the British ship, but Margaretta surrendered after James Moore was mortally wounded.
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.
- 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.
- Bangor and Aroostook Railroad bicentennial locomotive number 1776 was named Jeremiah O'Brien
- Giambattista, M. D., LCDR USN (February 1970). "Captain Jeremiah O'Brien and the Machias Liberty". United States Naval Institute Proceedings.
- Smith, Joshua M. Borderland Smuggling: Patriots, Loyalists, and Illicit Trade in the Northeast, 1783-1820 (Gainesville: University Press of Florida, 2007).
- Weld, Gardner Allen. A Naval History of the American Revolution" 1913 account of O'Brien capture of the Margaretta-see .pp.8-12
- Bangor and Aroostook Railroad Historical and Technical Society The BAR Newsletter June 1976 volume III, issue 2, pages 2&3