Maria Rosetti (born Marie Grant; 1819 – February 25 [O.S. February 13] 1893) was a Guernsey born Wallachian and Romanian political activist, journalist, essayist, philanthropist and socialite. The sister of British diplomat Effingham Grant and wife of radical leader C. A. Rosetti, she played an active part in the Wallachian Revolution of 1848. She was also noted for her enduring friendships with the painter Constantin Daniel Rosenthal and with Pia Brătianu, the wife of National Liberal politician Ion Brătianu. The Rosettis were parents to three sons: Mircea, Vintilă and Horia, all of whom were noted for their political activities.
Born to Captain Edward Grant, a ship-owning resident of Guernsey, and his Guernsey wife Marie Le Lacheur, Marie belonged to the Church of England. The Grants, who eventually settled in Plymouth, claimed lineage from the Scottish Clan Grant of Cannon, but this is uncertain.
In 1837, her younger brother Effingham was appointed secretary of Robert Gilmour Colquhoun, the British consul in Wallachia; soon after, Mary herself arrived in Bucharest, where she began work as a tutor. It was then that she met Rosetti, Effingham Grant's close friend and a member of the Rosetti family of boyars, who fell in love with her. Mary Grant was employed by the family of Wallachian Militia Colonel Ioan Odobescu, and gave lessons to his children—including his son Alexandru, the future writer and politician. At the time, she was residing in the Bucharest area around Curtea Veche.