Sarah Wentworth Apthorp Morton (1759 – May 14, 1846) was an Americanpoet.
She was born in Boston to a successful merchant family (descended from Charles Apthorp) on her fathers side and John Wentworth (Lieutenant-Governor) on her mother's side. In 1781, she was married to Boston lawyer Perez Morton at Trinity Church, Boston, and the couple lived on a family mansion on State Street. The marriage began to deteriorate by 1788, however, when an affair between Perez and Sarah's sister Frances (Fanny) became public. The family backlash led to Frances' suicide. The couple were later reconciled, but Sarah lost three of the five children she carried.
In 1796, the couple moved to Dorchester. From an early age, Sarah had begun writing poetry, but until 1788 her works had only circulated among her friends. She began publishing under the pen name Philenia, and her first book was printed in 1790. Her work was widely acclaimed, with Robert Treat Paine, Jr., in the Massachusetts Magazine dubbing her the "American Sappho". In 1792, she wrote an anti-slavery poem entitled "The African Chief", which was, in fact, an elegy on a slain African at St. Domingo in 1791.