After marrying Catherine Sunter when aged 28 and encouraged by his early cameos he went into business in Glasgow and then Edinburgh attracting clients that included Sir Walter Scott.

[3] It was said that a commission from Princess Charlotte of a portrait medallion inspired Henning to realise that he could use his drawings to create slate moulds that could be used to reproduce the friezes in miniature.

[4] In 1827, Henning and his son created sculptures in the style of the Parthenon frieze for a screen erected at Hyde Park Gate in London.

The following year, John Jr. confirmed that he would recreate a copy of the Parthenon frieze for London's Athenaeum Club.

Although only just over half the length of the 524 feet long original this model was at the correct scale and was constructed from Bath stone in agreement with Decimus Burton, the club's architect.

Henning found that they were very popular but the business was captured across Europe by others who had unauthorised copies of his work.

Trial proofs were made but unfortunately his partner in the enterprise, Alfred Robert Freebairn (1794–1846), died before either of the works were completed.

He won the Society of Art's Silver Isis Medal for a relief entitled "The Good Samaritan".

Another son Archibald Skirving Henning became an artist and he has a few paintings in public collections in the United Kingdom.