THE UMAYYAD REGIME 183by the Berber forces at Tarragona. Once attempts to retain or expand
a hold north of the Pyrenees had been given up, as the result of
Frankish resistance and also the establishment of settled government
under the Umayyads, the Islamic state centred itself firmly in the
Guadalquivir valley. The heart of Al-Andalus corresponded roughly
with the former Roman province of Baetica, with a large and fre-
quently disturbed frontier region established to the north of it, right
across the middle of the peninsula. As in the general expansion of
the Arab Empire, Islamic Spain found its own limits. This was partly
determined by the bounds of what it was possible to hold down
effectively by force, and partly by what could be transformed by
acculturation, the latter being a substantially smaller area than the
former, but in neither case extending to the whole of the peninsula.
Perhaps in this lay the seed of the ultimate destruction of Al-Andalus.
The Arabs were patently less successful than their Roman and
Visigothic predecessors in solving the problems of the assimilation of
the northern regions of the peninsula. However, their difficulties
were far greater in terms of what they had to achieve in the south,
where they eventually proved themselves eminently successful. Also,
being at the very extremity of the Islamic world, their interests were
not as greatly involved in the north, where communications over the
Pyrenees were of much less importance than they had been for the
Romans and the Goths. Africa and the eastern Mediterranean were
the more natural areas of concern for the Umayyads.
As a result, the tiny Asturian kingdom, lodged behind the moun-
tains, was able to expand, first by merging its ruling family with that
of the dynasty of the Dukes of Cantabria to the east, and then by
extending itself westward into Galicia. Similarly, at the tum of the
eighth century, as a result of Frankish activity from Aquitaine, a minute
independent realm was able to come into existence at Pamplona, and
the Franks were able to create a march at the eastern end of the
Pyrenees extending south to Barcelona, and also a county in the
valley of the river Aragon. The society and subsequent history of
these areas will be examined in a later chapter. For now it is important
to note that the problems they represented to the Umayyads were
similar to those that had faced the Visigoths, in the forms of inde-
pendent mountain-dwellers and Frankish aggression; secondly, that
significant transformations had taken place in these regions. The
kingdoms of the Asturias and of Pamplona were more complex so-
cieties than the earlier confederacies of Cantabrian and Basque tribes,