[1][2][3] After working briefly in the Foreign Office,[2] Nelson was appointed a lecturer at King's College, London, in 1970, promoted to Reader in 1987, to Professor in 1993, and Director of the Centre for Late Antique and Medieval Studies in 1994, retiring in 2007.

[4] Although she had studied under Ullmann, in 1977 she published an article critiquing his work, which she saw as overly sympathetic to the Carolingian Empire's administrative bureaucracy.

Instead, Nelson argued that Ullman had overestimated the Empire's ability or sophistication to reform itself as he had earlier proposed, thereby casting doubt on the decisiveness of the Carolingian Renaissance.

[7] The Jinty Nelson Award for Inspirational Teaching & Supervision in History was established by the Royal Historical Society in January 2018.

She published widely on kingship, government, political ideas, religion and ritual, and increasingly on women and gender during this period.

[10] Reviewing the book for the Financial Times, historian David Bates said, "Rigorous assessments of difficult evidence are mixed with what feels like invitations to conversation.