THE UMA YYAD REGIME 187
tyrant and shedder of blood'.5 Exemplary punishments could be
inflicted. The heads of defeated rebels were usually displayed on the
gates of Cordoba, and those of Christians killed in the Umayyads'
expeditions to the north were sent back to the capital for exhibition,
but the crucifixion of the father of a rebel leader with his son's head
hanging around his neck was unusually savage. However, such meth-
ods failed to reverse an ever-increasing spiral of violence that reached
its culmination in the reign of the Amir 'Abd-Allah (888-912), whose
authority was at times restricted to just the city of Cordoba.
The problems of order that the Umayyads faced were of several
different kinds. The more or less straight-forward rebellions aimed at
local autonomy occurred principally in the frontier zones, where the
independence and power of the governors was greatest and where
the fortified cities could hope to defy the retaliation of the amirs.
Toledo was one of the most consistently rebellious of these cities,
revolting in 761, 784-6, 788, 797, 872, 873 and 887, as well as suc-
cessfully maintaining its freedom, despite attempts at suppression
throughout the years 829 to 837, and 853 to 857 or later. Merida was
another centre of revolt in the years 807-8, 810-812, 828 (twice) and
- It too, after the second revolt of 828, enjoyed a period of inde-
pendence from external control in the years 828 to 833. Only the
destruction of its fortifications in 868, on the orders of the amir
Mul)ammad I, and the rise of Badajoz further down the Guadiana,
finally undermined its resistance and sent the city into an irreversible
decline.^6 The Ebro valley and Catalonia were also often centres of
urban rebellions, as in Zaragoza in 781-2, 788-92, 797-800, 802,
843-4 and 881, Barcelona in 788 and Huesca in 800.
The aims and causes of these revolts were varied. Some resulted
from internal tensions between mutually hostile sections of the local
populace, as in some of the outbreaks in Merida, where hostility
between Arabs, Berbers, muwallads and Christians was a frequent cause
of disturbance which could escalate into rebellion against central
authority. Little as we know of the details, such popular revolts may
be similar to that of Cordoba against the Visigothic monarchy in the
mid sixth century.
Personal ambitions and even dynastic disputes could manipulate
local susceptibilities in the search for a base from which rebellion
could be launched. The displaced elder brothers of Hisham I gained
enough support in Toledo in 788 to make it the centre of their revolt
against the new amir.' Merida, already the base for Ylisuf al-Fihri's
