From the research published by the Seven Dials Trust: "Zaehnsdorfs was founded in London in 1841 by Joseh Zaehnsdorf. In 1862 he received an honourable mention at the London International Exhibition. By the 1860s and 70s he was picking up medals all over Europe. In the summer of 1890 the company moved to purpose-built premises in Cambridge Circus, Soho {where the relief is}. They prospered and were granted The Royal Appointment to King Edward VII in 1901."
Wikipedia adds: Joseph Zaehnsdorf (1816–86) came to London in 1837, already a trained bookbinder. He worked for two companies and then " ...1844 ...he commenced business on his own account at 2 Wilson Street, removing in 1856 to 30 Brydges Street, Covent Garden, afterwards called 36 Catherine Street. Zaehnsdorf became a naturalised British subject in 1855, and died at 14 York Street, Covent Garden, on 7 December 1886." His only son Joseph William Zaehnsdorf took over the business and it must have been he that had 144 Shaftesbury Avenue built.
All you need to know about bookbinding.
