granting of simple charters of protection which were of no very great
significance. But now it is exemption from public burdens, etc., that
is made prominent, in addition to a complete severance from all
jurisdiction and control of the secular power of the _civitas_ in
which the bishop's see and domains are situated. That this concession
also was sought by the bishop on the plea of protection for his
dependents from oppression and exaction, does not diminish its
importance; for it is easy to see that the line which separates
recognized right of protection from recognized right of jurisdiction
is one easily effaced, and defense from the tyranny of a foreign power
can with little difficulty be transformed into domination by the
professed defender.

That this was the order of development consequent on these changes is
proved by the temporal dominion gained by the bishops in the next
century; and the steps of its growth marked by numerous immunities
granted by Charles the Bald, Karloman[94] his successor, and Charles
the Fat, the last of the Carlovingians in Italy. As a good example of
the complete development of this advance gained by the bishops, I will
mention a charter given by Charles the Fat to John, bishop of Arezzo,
in the year 879, in which he confirms to him all the property and the
rights of that see, and takes him under his protection, "sub
immunitatis suae defensione": he then goes on to explain what this
term meant, giving a full account of the extent to which a bishop's
property was exempted from the jurisdiction of the _judex publicus_,
and protected from the imposition of burdens and exactions.[95]

The next step in the growth of the episcopal power, and the most
important of all, is the progress from exemption to privilege, to
jurisdiction; and occurs after the return of the kingship of Italy to