From the mountains of Iran to the heart of the caliphate
In the 10th century, the Islamic world was far from having a single power; the old Abbasid Caliphate, with its capital in Baghdad, remained a religious and political point of reference, but its real authority had weakened, and in various regions, local rulers, independent armies, and new dynasties emerged, taking advantage of that fragmentation.
Against this backdrop, the Buyids appeared—a family of Persian origin from Daylam, a mountainous region located south of the Caspian Sea. Among them, the three brothers who built their power were Ali, Hasan, and Ahmad, sons of Buya, who had started as soldiers and gathered troops until they became military lords capable of conquering territories.
Their rise began in 934, when Ali managed to seize Fars, an important region in southwestern Iran, and established his power around Shiraz, but the decisive moment came the following year, when in 935, Mardavij, a powerful ruler of the Ziyarid dynasty, died, and his domains were plunged into instability. It was then that the Buya brothers took advantage of the power vacuum to advance rapidly.
The day the Buyids entered Baghdad
Over the following years, the three brothers expanded their domains: Hasan extended his authority over central Iran and came to control Isfahan and Rayy, while Ahmad advanced to the west.
The expansion culminated in 945, when Ahmad entered Baghdad, the capital of the Abbasid Caliphate, an event that completely changed the political balance, for although the Abbasid caliph remained on the throne, he lost much of his effective power, as the Buyids agreed to maintain the figure of the caliph and respected his religious authority, while they actually controlled the government and the army.
Ahmad then received the title of "emir of emirs," becoming the primary political authority in Baghdad, and although the new rulers were Shiites, while the Abbasid caliphate belonged to the Sunni tradition, the Buyids did not eliminate the caliph nor formally replace the caliphate with another religious power, but rather maintained that institution while making it clear that political power was in their hands.
Buyid rule reached one of its moments of greatest splendor under Adud al-Dawla, who governed in the second half of the 10th century and managed to unite vast areas of Iran and Iraq under his authority. His era was marked by cultural activity, public works, and the development of cities like Shiraz, which became one of the great centers of medieval Persia.
A power that ended up divided
The problem arrived after the death of Adud al-Dawla in 983, when disputes between his successors weakened the unity of the Buyid territories, as the different family branches began to act with greater autonomy and other regional powers took advantage of the situation to advance upon their domains.
The dynasty managed to hold on for several decades, but eventually, a new power appeared from Central Asia: the Seljuks.
In 1055, the Seljuk sultan Tughril Beg entered Baghdad and put an end to Buyid political dominance over the capital.
Even so, it is undeniable that, by then, the Buyids—who had risen to power from a mountainous region of Iran and ended up controlling western Persia, Iraq, and Baghdad itself—had seen a rise that signified one of the great transformations of the medieval Islamic world: the caliph retained his religious prestige, but effective power passed into the hands of a Persian dynasty that had built its strength through war, conquest, and the skillful use of existing political structures.
