Born in Sausalito, CA on Jan. 15, 1885. She did not like her given name of Euphemia, and came to be known to friends as "Effie" and usually signed her paintings "Charlton," the family name of her grandmother. While in her teens Fortune studied art at Edinburgh College of Art in Scotland and St John's Wood School of Art in London. Returning to California in 1905, she studied at the Mark Hopkins Institute under Arthur Mathews followed by work at the Art Students League of New York City under DuMond, Mora, Sterner, and Chase.

Many of her early works were destroyed when the family home in San Francisco was dynamited during the disaster of 1906. Early in her career she concentrated on portraiture; however, it was her landscapes and harbor scenes which brought her international acclaim. She lived and worked in Europe during three periods between 1897-1927. In California her energies were divided between her studio-home in San Francisco at 1254 Hyde Street and the Monterey Peninsula. One of the first artists to introduce the bright palette of Impressionism to California in the early part of this century, her style was considered modern by conservatives.

Fortune was a devout Catholic and in 1928 founded the Monterey Guild which was dedicated to ecclesiastical art. In the mid-1930s she abandoned easel painting for the liturgical arts and, with nine other artists, decorated over thirty Catholic churches across the country. In 1956 she received the Gold Medal Pro Excelsior et Pontifice from Pope Pius XII for her mosaic adornment of the Cathedral of the Immaculate Conception in Kansas City.

Fortune never married, and died in Carmel on May 15, 1969.