Born in New Haven, Connecticut, Loop came from a distinguished family, counting among her ancestors Roger and Oliver Wolcott.

[1] Her first studies took place in her native city under Louis Bail, later continuing under George Henry Durrie and Wales Hotchkiss, and she set up practice as a portraitist in her hometown, where she was known for painting from life.

[1] She moved to New York in 1863 to continue her studies under Henry Augustus Loop, whom she married in 1864; the couple then toured Europe, visiting Paris, Rome, and Venice, and showed work at the Paris Salon of 1869.

[2] She was elected as an associate of the National Academy of Design in 1873, but never became a full member, missing out by one vote in 1876.

[1] Nevertheless, she continued showing at the Academy, where she had first exhibited in 1866 and 1867; having taken a break until 1871, she rarely missed an annual thereafter until 1905.