After Thomas Gainsborough, English, 1727 to 1788, full length portrait in oil titled The Blue Boy. Signed lower right. Framed. Circa the late 20th century. The original was finished in 1770 and is owned by The Huntington in San Marino, California. Thomas Gainsborough was a portrait and landscape painter, draftsman, and printmaker. Along with his rival Sir Joshua Reynolds, he is considered one of the most important British artists of the second half of the 18th century. He is credited as the originator of the 18th century British landscape school. Gainsborough was a founding member of the Royal Academy. Portrait Paintings And English Art Collectibles.