Born Jessie Jane Meriton White, she was the daughter of Thomas White and Jane Teage Meriton of Gosport, Hampshire, England. She married Alberto Mario in 1857 at her family's home in England. Upon her return to London in the spring of 1855, Jessie applied to medical schools with the hope of becoming a doctor — some (Edwin Pratt in Pioneer Women in Victoria’s Reign, for one) have said she was the first woman in England to do so. All her applications were rejected because of her gender. She became a propagandist for the Italian cause working with Giuseppe Mazzini, then in exile in London. She wrote newspaper articles explaining the issues in Italy, gave lectures and raised funds for the Italian cause in northern England and Scotland. Jessie made her living writing. Jessie’s career as a journalist had started in England writing for British newspapers (Litta Visconti Arese in his introduction to The Birth of Modern Italy, says Jessie was the first woman journalist in England.) She also wrote for newspapers in the United States and Italian press. Starting in 1866 the first of what would be 143 articles over 40 years appeared in The Nation published weekly in New York. She was also a frequent contributor to Nuova Antologia a semi-monthly magazine published in Florence. (Rossella Certini [see below] has written that Jessie was the first journalist in Italy to explore the ‘cracks’ in the Italian reality.) Writing was also a way of expressing her passion for Italy and its people. She wanted to make sure that some of the lesser known heroes of the Risorgimento were not forgotten. She wrote biographies of Garibaldi and Mazzini, to be sure; but also biographies of Dr. Agostino Bertani, Carlo Cattaneo (with Alberto Mario), Giuseppe Dolfo, Alberto Mario (with Giosuè Carducci), Giovanni Nicotera. She was gathering material for several more at the time of her death. She is mentioned in an 1859 letter from Frances to Lazette (18590112FMS_LMW). "...among them Signora Jessie Meriton Mario who gives lectures in Italy. As Greeley says in a letter of introduction to me “My Italian English friend who lives & labours for the liberty of the country of another..."