Robert fitz Ranulf de Alfreton is best known for his donations to Beauchief Abbey in expiation for his involvement in the murder of Thomas Becket, Archbishop of Canterbury, in 1170.

There is some ongoing dispute in this regard, as the four murderers of St. Thomas are well known, as Robert fitz Ranulf is not found among them. Most likely, as with Sir Ranulf de Broc of Catteshall, Surrey and Frobury, co. Hants., Robert fitz Ranulf was involved in the conspiracy against Becket in some manner, the details of which are no longer known.

Founder of Beauchief Abbey ca. 1172-1176, in expiation for his involvement in the plot and murder of Thomas a Becket, archbishop of Canterbury.

"Of Robert Fitz-Ranulph, canon and founder of this place, who gave us four churches, namely, Norton, Alfreton, Wymmdeswold, and Edwalton, for whom a solemn service shall be said in the convent, and of Robert de Chaworth ."[Commendations of Beauchief Abbey"

Robert de Alfeton, Lord of Alfreton, Norton and Marnham, a grandson of Robert fitz Ralph, founder of Beauchief Abbey.