The ecclesiastical courts applied the canon law, a subcategory of the Civil Law as defined. These courts dealt with the clergy and personal matters including matrimony and probate. While the jurisdiction of the ecclesiastical courts was eventually transferred to the common law courts in the 19th century, the canon law influenced equity before then,which, in turn, later became a part of the Common Law.
A few thoughts.
1) Roman Law != Canon Law.
2) I am not willing to concede that Canon Law is the basis of Common Law. I will, however, concede that Canon Law influenced Common Law. (Canon law include laws of matrimony and probate after all, and these areas were originally outside the King's dominion.
However, influence is slippery term. Certainly Canon Law influenced Henry VIII decision - but I'm not sure I'd argue that that they were based of Canon Law. :-)