I apologise for the wide spread of time which this subject requires to outline the thread of connection between the Medieval Folk Fool and that of the published Mumming texts.
Firstly, the existence of Fools in seasonal customs in England has to be established. Theological disapproval provides oblique proof through its condemnation and illustrations in Psalters show that Fools did enjoy the position of ringleader for games, tricks and plays; particularly at Shrovetide.
Shrovetide is one season when puddings were eaten and by the sixteenth century a large crop of pudding epigrams – frequently satirical though obscure today – had developed. This paper shows how the folk Fool became known as Jack Pudding and that this name superceded that of Fool itself. As is known, in the sixteenth century, the Fool rose briefly to a respectable position as a theatrical entertainer. The evidence shows that he did not disappear at the onset of the Civil War, but still survived, in the Fool's coat, in fairgrounds and with travelling entertainers.
The crucial point I hope to make is one which requires more detail than there may be time for. In the fairgrounds a mutually beneficial relationship between mountebanks and their Jack Puddings grew up. So much so that sometimes the Fool had the leading part and sometimes the doctor, whose main source of income was not through the sale of the medicines or 'pacquets', but through the entertainment value they gave. The one collection of mountebank speeches, printed twice, shows that political and religious satire was a large part of their attraction. I have found one example (19th century) of dialogue between mountebank and Fool, which shows the Fool undermining the doctor's pretensions. This dialogue is similar to the Mumming dialogue between the Doctor and his servant Jack and I hope it may be possible to show that the mountebank and his servant, who was originally a seasonal folk Fool, were reabsorbed into the mumming play.