ts. Before his coronation as emperor, Charles had entered into
communications with the caliph of Bagdad, Harun-al-Rashid, probably in
order to protect the eastern Christians, and in 801 he had received an
embassy and presents from Harun. In the same year the patriarch of
Jerusalem sent him the keys of the Holy Sepulchre; and in 807 Harun not
only sent further gifts, but appears to have confirmed the emperor's
rights in Jerusalem, which, however, probably amounted to no more than
an undefined protectorate over the Christians in that part of the world.
While thus extending his influence even into Asia, there was scarcely
any part of Europe where the power of Charles did not make itself felt.
He had not visited Spain since the disaster of Roncesvalles, but he
continued to take a lively interest in the affairs of that country. In
798 he had concluded an alliance with Alphonso II., king of the
Asturias, and a series of campaigns mainly under the leadership of King
Louis resulted in the establishment of the "Spanish march," a district
between the Pyrenees and the Ebro stretching from Pampeluna to
Barcelona, as a defence against the Saracens. In 799 the Balearic
Islands had been handed over to Charles, and a long warfare was carried
on both by sea and land between Frank and Saracen until 810, when peace
was made between the emperor and El-Hakem, the emir of Cordova. Italy
was equally the scene of continuous fighting. Grimoald of Benevento
rebelled against his overlord; the possession of Venice and Dalmatia was
disputed by the two empires; and Istria was brought into subjection.

With England the emperor had already entered into relations, and at one
time a marriage was proposed between his son Charles and a daughter of
Offa, king of the Mercians. English exiles were welcomed at his court;
he was mainly instrumental in restoring Eardwulf to the throne of
Northumbria in 809; and Einhard includes the Scots within the sphere of
his influence. In eastern Europe the Avars had owned themselves
completely under his power in 805; campaigns against the Czechs in 805
and 806 had met with some success, and about the same time the land of
the Sorbs was ravaged; while at the western extremity of the continent
the Breton nobles had done homage to Charles at Tours in 800. Thus the
emperor's dominions now stretched from the Eider to the Ebro, and from
the Atlantic to the Elbe, the Saale and the Raab, and they also included
the greater part of I