Roussel was born in Brittany and educated in Paris. In about 1874 he moved to England, where he remained for the rest of his life. He was married twice, both times to an Englishwoman. He lived for many years in Chelsea where he became a member of Whistler's circle and a highly regarded painter. He was aged about 40 when he began etching and Whistler influenced him greatly. In all he produced about 170 etchings. He became fascinated by colour etching and became a master in this art. He designed his own elaborate frames for his colour prints and these, in original frames, are today highly prized collectors' items. He made small editions of his prints and they are relatively scarce. His companion in later life, Agnes Mackay compiled a catalogue of his prints which remained unpublished. In 1991 the Margaret Hausberg catalogue of his prints was published.