Nathaniel Hubert John Westlake (N H J Westlake) FSA (1833–1921) was a 19th-century British artist specializing in stained glass.
Westlake began to design for the firm of Lavers & Barraud, Ecclesiastical Designers, in 1858, and became a partner ten years later, making the firm Lavers, Barraud and Westlake, of which he became sole proprietor in 1880. The firm was then known as Lavers & Westlake.
A leading designer of the Gothic Revival movement, his works include The Vision of Beatrice (1864), commissioned for an exhibition of stained glass held at the South Kensington Museum (renamed the Victoria and Albert Museum in 1899).
In 1896, Lavers & Westlake were commissioned to reglaze two central lights in the great hall windows at Mary Datchelor Girls' School, Camberwell. The subjects were 'Lady Jane Grey discourses with Roger Ascham' and 'By Industry and Perseverance', symbolising the importance of female endeavour in higher education. Other windows included 'On the way to Chapel', 'Physical Exercise', 'The Kindergarten' and 'The Classroom'. The windows were removed from the school in 2010 after it was converted into a series of apartments.
Westlake published under the name of "Nat Hubert John Westlake".