The younger sister of James Otis, Boston’s leading advocate for colonists’ rights in the 1760s, Mercy was a bookish girl in a time when many girls never obtained basic literacy. Her father, James Sr., encouraged her curiosity. She demanded to join in when her brothers read aloud and took the place of her second-oldest brother during lessons with their uncle, a local minister. While James was a student at Harvard, he’d come home and tell her about his studies, especially the political theories of John Locke. She read voraciously: Shakespeare and Milton, Greek and Roman literature, Moliere’s plays in translation, Sir Walter Raleigh’s History of the World. At age 14, she met her future husband, James Warren, at her brother’s Harvard graduation. They married in 1754 at ages 26 and 28, respectively. While raising five children, she began writing private poems about family and nature.
In the 1760s, the Warrens’ Plymouth home became a meeting-place for like-minded patriots. Her husband joined her brother in the Massachusetts legislature—together, they opposed colonial governor Thomas Hutchinson. But James Otis’ career was cut short in 1769, when a British customs officer bashed his head with a cane in a bar brawl and the trauma pushed him into mental illness.
After Otis went mad, his sister began answering his correspondence, including letters from radical British historian Catharine Macaulay. Encouraged by her husband, who praised her “genius” and “brilliant and busy imagination,” Warren also began writing satirical plays that attacked Hutchinson, her brother’s nemesis. Her first play, The Adulateur, published in Boston’s Massachusetts Spy newspaper in March and April 1772, portrayed a thinly disguised Hutchinson as Rapatio, the dictatorial leader of the mythical kingdom of Servia. Warren pitted Brutus, a hero based on her brother, against Rapatio. “The man who boasts his freedom,/Feels solid joy,” Brutus declared, “tho’ poor and low his state.” Three years before the Revolution, Warren’s play warned that a day might come when “murders, blood and carnage/Shall crimson all these streets.”
The Adulateur caught on with Boston’s patriots, who began to substitute its characters’ names for actual political figures in their correspondence. Then, in 1773, Boston newspapers published private letters of Hutchinson’s that confirmed patriots’ worst suspicions about him. (In one, Hutchinson called for “an abridgement of English liberties in colonial administration.”) Warren responded with The Defeat, a sequel to The Adulateur, which cast Rapatio as the “dangerous foe/Of Liberty of truth, and of mankind.”