In her youth, Barker exchanged verse with other amateur poets, including a group of scholars at St John's College, Cambridge. Throughout her nearly 50 year writing career, she wrote "friendship epistles, odes, satires on affairs of state, religious dialogues from a Catholic perspective, and poetry on medical themes, as well as her novels." The DNB aptly summarizes her literary significance: "As a coterie and then court poet turned market place novelist, she exemplifies the emergence of female literary professionalism, her long and diverse writing life illustrating the shift from an amateur, court-centred manuscript-based literary system to the market-driven culture of print. She is an important Jacobite imaginative writer as well. Her verse-history ?Poems Refering to the Times? is a key Jacobite poetic text of the 1690s, while the later novels offer a sustained Catholic?Jacobite response to the declining fortunes of the Stuarts during the early Hanoverian period."