Joanna Hiffernan (ca. 1843 – after 1903) was an Irish artists' model and muse who was romantically linked with American painter James Abbott McNeill Whistler and French painter Gustave Courbet. In addition to being an artists' model, Hiffernan herself also drew and painted.
Hiffernan was a Roman Catholic. Her father, Patrick Hiffernan, is described by Whistler's friends, Joseph Pennell and his wife Elizabeth, as being like "Captain Costigan," the drunken Irishman in Thackeray's novel Pendennis. The Pennells also described him as "a teacher of polite chirography (calligraphy)" who used to speak of Whistler as "me son-in-law." Her mother, Katherine Hiffernan, died in 1862, aged 44. Joanna Hiffernan had a sister called Bridget Agnes Hiffernan, later Singleton. The artist Walter Greaves, who began tuition with Whistler in 1863, and who knew Hiffernan well, said that she had a son called Harry but no trace of him can be found in official records.
Whistler first met Hiffernan in 1860 while she was at a studio in Rathbone Place, and she went on to have a 6-year relationship with him, during which period she modelled for some of his most famous paintings. Physically striking, Hiffernan's personality was even more impressive. Whistler's biographers and friends, the Pennells, wrote of her,
She was not only beautiful. She was intelligent, she was sympathetic. She gave Whistler the constant companionship he could not do without.
Whistler's family did not approve of Hiffernan. Unmarried artists' models, and especially those who posed nude, were considered at that time to be little better than prostitutes. However, Hiffernan seems only to have modeled for friends, so perhaps the objections to her made by Whistler's family were based more on social class than on Hifferman's personal character. When Whistler's mother visited from America in 1864, alternative accommodation had to be found for Hiffernan, who also seems to have been the cause of Whistler's quarrel with Alphonse Legros in 1863.