He first attended Leicester Academy, and then entered Dartmouth College, where Moore taught languages, at the age of thirteen.

[4] Washburn was elected to the Massachusetts House of Representatives in 1826, serving two terms; his only notable activity was in committee work preparing a feasibility study for a railroad from Boston to the Connecticut River.

[7] During these years he also established and maintained what was described by one of his peers, George Frisbie Hoar, as one of the largest and most successful law practices in Worcester County,[8] partnering with John Davis among others.

[13] During his one year in office, he successfully promoted and enacted significant pieces of legislation on a broad social welfare agenda, including measures concerning debt relief, assistance to the poor and insane, and financial aid for female medical students.

[10] One major event that took place during Washburn's tenure was Anthony Burns' arrest and trial under the terms of the Fugitive Slave Law of 1850.

The case galvanized anti-slavery activists, who protested outside the courthouse and sought both legal and extra-legal remedies to secure Burns' release.

Washburn stood for reelection, but the Whig party apparatus was generally unaware of Know Nothing strength and dismissive of its candidates.

One commentator described the Know Nothing slate as "spavined ministers, lying tooth-pullers, and buggering priests", and Washburn's opponent, former Whig Henry J. Gardner, as a "rickety vermin" who stood no chance of winning.

The seat had previously been occupied by Judge Edward G. Loring, who Harvard's Overseers refused to retain after he ruled that Burns be returned to slavery.

For the next twenty years, Washburn served as one of three dominant figures (along with Theophilus Parsons and Joel Parker) in shaping the law school's practices and curriculum.

When the American Civil War broke out in 1861, Washburn led calls for harmony in the law school, which had students from both northern and southern states.

[22] He also served, despite his relatively advanced age, in a home guard militia unit, and supported the war effort by writing, giving speeches, and donating money.

Biographer Robert Spector describes it as "the starting point and basis" for legal historical work relating to the court.

[28] Washburn considered himself to be more of an antiquarian than a historian: he believed it important to conserve artifacts and historical information, leaving the interpretation of those to others.