(1778-1858) a U.S. Representative; born in Machias, on January 21, 1778. He attended the common schools, then engaged in lumber manufacturing and in shipping.
A member of the Maine State Senate 1821-1824, he was elected to the Eighteenth, Nineteenth, and Twentieth Congresses (March 4, 1823-March 3, 1829). O’Brien was chairman of the Committee on Expenditures in the Department of the Navy (Nineteenth Congress), but was an unsuccessful candidate for reelection in 1828.
Later he became a member of the Maine House of Representatives (1832-1834), then resumed his former lumber manufacturing and shipping business.
He died in Boston on May 30, 1858, with interment in O’Brien Cemetery in Machias.