Marjorie Morgan McCallum Chibnall OBE FBA was an English historian, medievalist and Latin translator.

She was educated at Shrewsbury Priory County Girls School and Lady Margaret Hall, Oxford, where she later became a Research fellow. She became a Fellow of Girton College, Cambridge, but relinquished the fellowship when she decided in 1965 to give up teaching to complete her editorial work on the Historia Ecclesiastica of Orderic Vitalis. Four years later she was made a Research Fellow and subsequently a Fellow of Clare Hall, University of Cambridge (and Honorary Fellow of Girton College, Cambridge. Earlier in her career she had taught at the University of Southampton and the University of Aberdeen. Chibnall's early research focused on medieval Normandy. Her career spanned more than six decades, and she continued to publish well into her 90's. Her last book, a brilliant short account of the Normans was published in 2006.

Marjorie Chibnall was an active participant at the Battle Conferences on Anglo-Norman history and an editor of their proceedings. She was a fellow of the British Academy. Her masterly edition of Orderic Vitalis was probably her greatest contribution to the study of the Anglo Norman period, but her biography of the Empress Matilda also attracts widespread admiration.