Kayqubād I ruled the Rûm Sultanate at its political and territorial peak, pushing borders toward the Mediterranean after taking Alanya in 1221 and securing Black Sea access through Sinop. Sivas functioned as a principal administrative city throughout his reign, and its mint output reflects the relative stability and ambition of the period — a sharp contrast to what came after the Mongol victory at Köse Dağ in 1243, which effectively ended Seljuk autonomy within a decade of his death.
Kayqubād I ruled the Rûm Sultanate at its political and territorial peak, pushing borders toward the Mediterranean after taking Alanya in 1221 and securing Black Sea access through Sinop. Sivas functioned as a principal administrative city throughout his reign, and its mint output reflects the relative stability and ambition of the period — a sharp contrast to what came after the Mongol victory at Köse Dağ in 1243, which effectively ended Seljuk autonomy within a decade of his death.