They are indeed founded upon the Materials for the History of Thomas Becket, which Canon Robertson had edited for the Master of the Rolls in the previous year.

They were of course read by every one, because they were written by Froude, whereas Robertson's learned Introduction would only have been read by scholars.

Froude's conclusions were much the same as the erudite Canon's.

He did not pretend to know the twelfth century as he knew the sixteenth, and he avowedly made use of another man's knowledge to point his favourite moral that emancipation from ecclesiastical control was a necessary stage in the development of English freedom.
He may have been unconsciously affected by his familiarity with the quarrel between Wolsey and Henry VIII.

in describing the quarrel between Becket and Henry II.