Cassatt was born in Pennsylvania into an upper-middle-class family that viewed travel as integral to education; she spent five years in Europe and visited many of the capitals, including London, Paris, and Berlin. While abroad she learned German and French and had her first lessons in drawing and music. Her family objected to her becoming a professional artist.
Cassatt began studying painting at the Pennsylvania Academy of the Fine Arts in Philadelphia. She said, "There was no teaching" at the Academy. Female students could not use live models, until somewhat later, and the principal training was primarily drawing from casts and Cassatt decided to end her studies and in 1866 moved to Paris, with her mother and family friends acting as chaperones. Since women could not yet attend the École des Beaux-Arts, Cassatt applied to study privately with masters from the school.
She returned to the US in the late summer of 1870 but had no success and considered giving up until the archbishop of Pittsburgh commissioned her to paint two works in Parma and covered her travel expenses to Europe. Within months of her return to Europe in the autumn of 1871, Cassatt's prospects had brightened. Her painting Two Women Throwing Flowers During Carnival was well received in the Salon of 1872, and was purchased. She attracted much favourable notice in Parma and was supported and encouraged by the art community there: "All Parma is talking of Miss Cassatt and her picture, and everyone is anxious to know her".
After completing her commission for the archbishop, Cassatt travelled to Madrid and Seville, where she painted a group of paintings of Spanish subjects, including Spanish Dancer Wearing a Lace Mantilla and in 1874, she made the decision to take up residence in France. Edgar Degas invited her to show her works with the Impressionists in 1874.
Cassatt admired Degas, whose pastels had made a powerful impression on her. She felt comfortable with the Impressionists and joined their cause enthusiastically and Degas had considerable influence on Cassatt. Both were highly experimental in their use of materials, trying distemper and metallic paints in many works, such as Woman Standing Holding a Fan, 1878-79. She became extremely proficient in the use of pastels, eventually creating many of her most important works in this medium. Degas also introduced her to etching.
After 1886, Cassatt no longer identified herself with any art movement and experimented with a variety of techniques.
She will be best remembered as one of a few women who broke through that male only glass ceiling and competed head to head with them on ability.