Like other 19th-century women historians, Green tended to concentrate her work in fields seen as suited to "feminine" talents: research into queens and ladies, private lives, and the deciphering, translation and compilation of historical documents, for instance. One of her earliest books was prefaced by her asking the reader not to criticise her for having "ventured upon a field usually occupied only by the learned of the opposite sex." Her calendar prefaces, though, were an opportunity to write on broader, more "masculine" themes, like the Interregnum, earning respect for the overall quality and "strict historical accuracy".