It was by Dante Gabriel Rossetti (1828-1882), a founder of the famous Pre-Raphaelite Brotherhood of young, mid-19th century British artists. He mostly painted what amounted to portraits of women in literary settings. He used various women for this purpose, and in his paintings, they all looked fairly similar, as we shall see.
The Wikipedia entry for Rossetti is here.
Regardless of who the model was, Rossetti usually transformed her into a woman with a long nose, a short upper lip/muzzle zone, a strong chin and a long neck. Also, her hair tended to be parted at or near the the center of her head and was usually long and wavy. Below are more examples of Rossetti's women along with photographs of the models.
Siddal (1829-1862) was Rossetti's wife, who died young.
She was Rossetti's housekeeper and mistress for many years.
She was married to William Morris of the Arts & Crafts movement. It seems that Rossetti was infatuated with her, and her looks tended to merge into the paintings he made using other models, as can be seen above.