150 EARLY MEDIEVAL SPAINpopulation into the ranks of the conquerors, the Arabs and their
freedmen could only by themselves constitute a portion of .the forces
needed to achieve the military success of their campaigns. In the
West this problem led to the employment of other far less well assimi-
lated groups of conquered population in extending the conquests
into new areas. Thus the Berber tribes, who had put up a strong if
ultimately unsuccessful resistance to the Arab conquest of much of
North Mrica for twenty years or more, provided the recruiting ground
for the expeditions sent into Spain in 711. Although one late source
implies that some of the Berbers who crossed into the Iberian penin-
sula were pagans, the logic of the Qu'ranic injunctions would have
required those who were associated with the Arabs in the conquests
to have become Muslims. It is notable that although conversion was
long delayed in those parts of North Mrica not overrun by the Arabs
in the period c. 680-711, in the conquered territories it appears to
have been relatively swift and permanent. The tribal organisation of
their society and the psychological impact of military defeat may have
made it easier for large-scale and rapid conversion to take place
amongst the Berbers.^13 Although no quantitative data survives that
would make it possible to know what percentage of the troops in-
volved in the conquest of Spain in the period 711-720 was of Berber
origin, it is notable that the crucial expedition of 711 was led by Tariq
ibn Ziyad, a Berber freedman and client of Musa ibn Nu~ayr, the
governor of Ifriqiya. That his father's name, Ziyad, was an Arab one
would suggest that Tariq was at least a second generation Muslim,
and that his family had been taken into clientage at a relatively early
stage of the Arab conquest of North Mrica. According to some sources
he was a member of the Nafza tribe, from the region of Tripoli.14 This
area had been conquered by the Arabs in 647. He himself led what
appears to be a predominantly or even exclusively Berber army, but
in the light of what is known of Tariq's own ancestry and origins, it
should not necessarily be assumed that these were drawn from the
recently conquered tribes of the central regions of North Mrica. They
are more likely to have been drawn, like Tariq himself, from tribes who
had been conquered and Islamicised anything up to half a century or
more earlier. Some of those conquered in the west in the first decade
of the eighth century might, however, have then been used in the
campaigns in Spain from 711 onwards. For, following the effective
subjugation of Ifriqiya, the old Roman province of Mrica centred on
Carthage and the new settlement of Kairouan, and the appointment