• Found tax base inadequate to support huge army and complex civil service
• Ex-soldiers seeking better salaries recognized different caliphs
  • The caliphs fought for power in savage civil wars
• For military support, many new rulers turned to independent military commanders
  • Many mamluks gained renown and some became rulers themselves
• In 945, caliphate fell under control of mountain warriors from Daylam
  • Abassid caliph remained, but Buyid princes controlled him
• In 1055, Turkish Seljuk family established Muslim state based on nomadic power
• In 1258, Abbasid caliphate in Baghdad was destroyed by Mongol invasions