William Warrington, who trained with Thomas Willement, worked independently from the early 1830s. He retired in 1866 but his firm carried on under his son, James Perry Warrington until c.1875. He had a short period working with AWN Pugin between 1838 and 1842, before the two fell out.
Warrington wrote one of the most important books on stained glass in the early years of its Victorian revival, “The History of Stained Glass, from the Earliest Period of the Art to the Present Time”, published in 1847. It was an important contribution, but despite Warrington’s championing of medieval style, he suffered from his disputes with ecclesiology and especially the members of the Cambridge Campden Society, who strongly criticised the book, and this held back his business.
Victorian Stained Glass by Martin Harrison (London : Barrie & Jenkins, 1980)
Stained Glass and the Victorian Gothic Revival by Jim Cheshire (Manchester University Press, 2004)
William Warrington on Wikipedia