In November 2016, screenwriter Sally Wainwright was awarded the £30,000 screenwriting fellowship grant from the charitable organisation the Wellcome Trust, in partnership with Film4 and the British Film Institute. Wainwright disclosed to the media that she was writing a drama series about the landowner, industrialist, and intellectual Anne Lister and would use the grant to further her research.
The title comes from a slur from the time period. "Gentleman" refers to Anne Lister's more masculine behavioral traits such as wearing dark and black clothing and her knowledge of subjects not usually studied by women at the time. "Jack" is term used then for dyke or lesbian (which wasn't a phrase back then).
The series is based on the collective diaries of Anne Lister's - containing over 4 million words and written largely in code.
Sally Wainwright, a native of Yorkshire, had grown up in the environs of Shibden Hall and had had ambitions to write a drama based on Anne Lister for over 20 years.
Sally Wainwright described Lister as "a gift to a dramatist" and "one of the most exuberant, thrilling, and brilliant women in British history."