She later became an author, publishing six novels under the name Katharine Lee, as well as writing books on Christian symbolism.

[citation needed] As well as pursuing her writing career, Jenner worked together with her husband on themes such as sacred art and the Cornish language revival.

Her husband had corresponded with her since 1873, when he interviewed her father about the Cornish language, a topic which later became a major research interest for the couple.

She was to publish five more novels, the last being When Fortune Frowns: Being the Life and Adventures of Gilbert Coswarth, a Gentleman of Cornwall; How he Fought for Prince Charles in the years 1745 and 1746, and What Befell Him Thereafter (1895).

[7] Jenner retold the story of the Jacobite rising of 1745 and the Battle of Culloden, The Times review commenting "she acquits herself with credit".

[6] Jenner and her husband were keen Jacobites, joining the Order of the White Rose as part of the Neo-Jacobite Revival.

[5] They returned to Jenner's home town of Hayle in 1909 and immersed themselves in Cornish culture, living in a house they called Bospowes.