potentates up to the Emperor himself: she claimed that princes were as
much subject to her jurisdiction as other laymen, and she did not
hesitate to make good that claim even to the excommunication of a
refractory ruler and--its corollary--the release of his subjects from
their oath of allegiance. Finally, the Church awoke a responsive echo
in the hearts of all those liable to oppression or injustice, when she
asserted a right of interposing in purely secular matters for the sake
of shielding them from wrong; while she met a real need of the age in
her exaltation of the papal power as the general referee in all cases
of difficult or doubtful jurisdiction.

Thus the claims of each power as against the other were not at all
commensurate. For while the imperialists would agree that there was a
wide sphere of ecclesiastical rule with which the Emperor had no
concern at all, it was held by the papalists that there was nothing
done by the Emperor in any capacity which it was not within the
competence of the Pope to supervise.




CHAPTER I

THE BEGINNINGS OF CHURCH REFORM


Previous to the eleventh century there had been quarrels between
Emperor and Pope. Occasional Popes, such as Nicholas I (858-67), had
asserted high prerogatives for the successor of St. Peter, but we have
seen that the Church herself taught the co-ordinate and the mutual