Prinsep was a close friend of John Everett Millais, and of Burne-Jones, with whom he travelled further in Italy. He had a share with Dante Gabriel Rossetti and others in the decoration of the hall of the Oxford Union. With other members of the Pre-Raphaelite Brotherhood, he taught at the Working Men's College during the mid-19th century. He first exhibited at the Royal Academy of Arts in 1862 with his "Bianca Capella", his first picture, which attracted notice as a portrait (1866) of General Gordon in Chinese costume. Prinsep lent the costume to Millais who used it in his own painting "Esther."