Saxon power by the conquest of Brandenburg, Lusatia, Strelitz and
Schleswig. These could only be called national services on the
assumption that the crown was to remain the hereditary possession of his
house; but the German kingship was elective. To the Church, however,
nothing was more welcome than conquests gained at the expense of heathen
Slavs and Danes. In her eyes this Saxon statesman was the forerunner of
the Christian faith in the dark places of Europe. For all these reasons,
then, the power of Henry and his successors remained a power resting
upon ecclesiastical support. To strengthen the alliance of church and
state must be the first object of a Saxon ruler.

For some years after his accession (936) Otto I was harassed by
pretenders of his own family who allied themselves with one or more of
the great Dukes. The Bavarians threatened to secede and form an
independent nation; the Franconians rebelled when their right of waging
private wars was called in question; the Lotharingians intrigued to make
themselves an independent Middle Kingdom. All such malcontents found it
easy to secure a brother or a son of the King as their nominal leader.
Even when Otto had placed all the duchies in the hands of his own
kinsmen or connections, his power was still precarious. For he claimed
new rights which, though necessary to the maintenance of kingly power,
did violence to feudal and provincial sentiment; while the Dukes whom he
nominated usually took up the pretensions of their predecessors, and
identified themselves with the interests of their subjects. It was more
important than ever that the King should have the help of the clergy in
educating public opinion. But in the most critical period (939-955) of
the reign the German primate, Archbishop Frederic of Mainz, lent the
weight of his influence and high personal reputation to the rebel cause.
In another direction also Otto found the clergy the chief opponents of a
cherished scheme. Organised missions were among the means on which he