Fashion designer Giuseppe Gustavo [Jo] Mattli was born in 1907 in Locarno where he grew up in a large family. Keen to develop a career in the growing fashion industry of the mid-1920s, Mattli moved to England in 1926 to learn tailoring skills. He then moved to Paris where he joined the House of Premet, founded in 1911. Trained and ready to produce his own collections, Mattli returned to London in 1934 and opened his couture house in fashionable Knightsbridge, sharing premises with fellow couturier Charles Creed. By August 1939 he was residing and working at no. 6 Yeomans Row.
Mattli created stylish couture outfits as well as ready-to-wear garments. Early success meant that by 1938 he was showing his collections in Paris, but further expansion was curtailed by the Second World War. In 1941/2 he joined the recently established Incorporated Society of London Fashion Designers, whose work included promoting their designs abroad, especially in America. Mattli was noted for his feminine evening and cocktail dresses and his style characterised by softly draped fabrics and easily wearable designs. In 1955, the company with whom Mattli worked went into liquidation, bringing to an end his couture line. He continued to produce ready-to-wear collections until the House of Mattli closed in the early 1970s. He died in February 1982.