After repeated defeats, each more crushing than the last, the imperial power, so far from being able to look down on the papal, could not even maintain itself on an equal footing. Against no pontiff since Gregory VII had the monarch's right to name or confirm a pope, undisputed in the days of the Ottos and of Henry III, been made good. It was the turn of the Emperor to repel a similar claim of the Holy See to the function of reviewing his own election, examining into his merits, and rejecting him if unsound, that is to say, impatient of priestly tyranny. A letter of Innocent III, who was the first to make this demand in terms, was inserted by Gregory IX in his digest of the Canon Law, the inexhaustible armoury of the churchman, and continued to be quoted thence by every canonist till the end of the sixteenth century[256]. It was not difficult to find grounds on which to base such a doctrine. Gregory VII deduced it with characteristic boldness from the power of the keys, and the superiority over all other dignities which must needs appertain to the Pope as arbiter of eternal weal or woe. Others took their stand on the analogy of clerical ordination, and urged that since the Pope in consecrating the Emperor gave him a title to the obedience of all Christian men, he must have himself the right of approving or rejecting the candidate according to his merits. Others again, appealing to the Old Testament, shewed how Samuel discarded Saul and anointed David in his room, and argued that the Pope now must have powers at least equal to those of the Hebrew prophets. But the ascendancy of the doctrine dates from the time of Pope Innocent III, whose ingenuity discovered for it an historical basis. It was by the favour of the Pope, he declared, that the Empire was taken away from the Greeks and given to the Germans in the person of Charles[257], and the authority which Leo then exercised as God's representative must abide thenceforth and for ever in his successors, who can therefore at any time recall the gift, and bestow it on a person or a nation more worthy than its present holders. This is the famous theory of the Translation of the Empire, which plays so large a part in controversy down till the seventeenth century[258], a theory with plausibility enough to make it generally successful, yet one which to an impartial eye appears far removed from the truth of the facts[259]. Leo III did not suppose, any more than did Charles himself, that it was by his sole pontifical authority that the crown was given to the Frank; nor do we find such a notion put forward by any of his successors down to the twelfth century. Gregory VII in particular, in a remarkable letter dilating on his prerogative, appeals to the substitution by papal interference of Pipin for the last Merovingian king, and even goes back to cite the case of Theodosius humbling himself before St. Ambrose, but says never a word about this 'translatio,' excellently as it would have served his purpose.