For more than half a century, between Aqa Muhammad Khan's reign and Nasir al-Din's accession in 1848, diverse forces accelerated or hindered the process of succession. Chief among them were intertribal divisions, tensions within the royal family, the wishes of the foreign powers, and the vested interests of the bureaucracy. Conscious of the ever-present threat of tribal discord, as early as 1789 Aqa Muhammad Khan stipulated that the crown should pass to the first son born of the bond between the two powerful clans of the Qajar house; the Quvanlu and the Davalu. Aqa Muhammad Khan's aspirations for the continuity of his empire were thus projected in the progenitive capacities of his successor. With similar considerations in mind, Fath 'Ali Shah married his son and celebrated heir, 'Abbas Mirza, to a daughter of Davalu. He also instructed other princes of the royal family to take brides from other Qajar branches.
Healing the age-old tribal rifts between the two chief branches of the Qajar tribe was no doubt the immediate aim for these unions. The ruling family was initially from the Quvanlu (or Quyunlu), the sheep clan that was the principal lineage of the six clans of the Ashaqah-bash ("the downstream settlers") subtribe of the Qajar tribe. By contrast, the Davalu, the camel clan, was the chief clan of the Yukhari-bash ("the upstream settlers").The hostility between the two clans intensified in the late eighteenth century. When the Qajars came to power, the memories of defections and betrayals that had cost the lives of three successive Quvanlu leaders and had caused much fratricide and bloodshed among the Qajars of Astarabad still rankled, especially in the minds of the mothers, sisters, and daughters of the slain warriors. Aqa Muhammad Khan's merciless struggle against his Qajar rivals, both Davalu and Quvanlu, further exacerbated these ill feelings.
Fath 'Ali Shah could not have fulfilled the expectations of his predecessor more fittingly. During the forty-seven years of his adult life, thirty-five of which he spent on the throne, he single-handedly generated a royal family of unprecedented size. He brought close to 1,000 wives of diverse origin, class, age, and function to his royal harem. He married not only the daughters of the Qajars and other tribal chiefs, including ex-wives of his paternal uncles, but also the daughters of high-ranking officials, merchants, and urban notables, women captured in wars with the remnants of the vanquished dynasties (the Afsharids and the Zands), Persian and Georgian slave girls, and a host of concubines, entertainers, and women servants who crowded the expanding inner quarters (andarun ) of the shah. They bore him offspring at a rate that truly made Fath 'Ali Shah one of the most fertile men in history. Between January and November 1789 alone, shortly after his official designation to apparency, his wives gave birth to no less than seven sons, three of whom (including 'Abbas Mirza) were born within ten days. By the time of his death in 1834, he left behind some sixty sons and more than forty daughters.
The record of Fath 'Ali Shah's children is no less impressive. His first ten sons, the most powerful princes of the royal house, had between them a total of 333 children: 175 sons and 158 daughters.The assessment of the court historian Sipihr, who placed the number of Fath 'Ali's surviving offspring in 1834 at 786, does not seem to be an exaggeration. "It is not implausible," he added, "that by now they have multiplied to ten thousand."Thanks to Fath 'Ali and his sons, in the relatively short period of half a century and over a span of five generations between Aqa Muhammad Khan and Nasir al-Din Shah a new royal nobility was created that could reduce to uneasy submission all rival forces, both within and outside of the Qajar tribe.
The aptitude of Fath 'Ali Shah and the royal princes to assemble households of such proportion certainly went beyond the boundaries of family love or lustful pleasure, the latter becoming the subject of frequent criticism and ridicule by later observers. In many instances, sheer political expediency was the only motivation to marry women of diverse tribal origins. These were wives whom the king and the royal princes often disliked for their odious arrogance but nonetheless tolerated for their worth as pawns, or hostages, in a complicated political game.[23] Union as such was an effective method by which to consolidate the Qajar throne. Discussing the high-ranking wives of his father, Ahmad Mirza 'Azud al-Dawla, the fortyninth son of Fath 'Ali Shah, noted: "It was merely for the peaceful unification of the tribes and clans, and for the expression of kingly mercy, that these wives became the subjects of royal favor and respect." For all the blame and criticism Fath 'Ali Shah often receives for his life of extravagance and pleasure seeking, he should be credited for transforming, largely by peaceful means, the Qajar tribe from a diffuse oligarchy with shaky loyalties into a closely knit patrimony.
The earliest attempts to enforce a rule of succession proved to be ineffective in relaxing the tension between the shah's numerous sons. Not until Nasir al-Din Shah's reign did the Qajars fully replace the custom of free and often bloody contest for succession with the norm of primogeniture. Although 'Abbas Mirza's nomination was seldom disputed openly by Fath 'Ali Shah himself, the crown prince was periodically challenged by his powerful brothers, who felt they were equally justified in their claim to apparency.
The system of provincial tutelage under Fath 'Ali in practice divided Iran among the senior princes of the Qajar house, allowing them to have their miniature court and administration and a large measure of independence in the conduct of their affairs. By the 1820s there were at least four other potential candidates for succession among the sons of the shah, three of whom were eligible because of their maternal Qajar lineage, their proximity in age to the crown prince, and above all their political leverage over the shah. Fath 'Ali himself, who increasingly felt the pressure brought on him by his sons, fostered a level of competition among them—a competition that was not without its later costs to the crown and the country.
Fraternal strife among the Qajar princes in turn introduced new factors into the process of succession, of which the most important was the prospect of foreign intercession. 'Abbas Mirza's position as the crown prince, the viceregent (na'ib al-saltana ), and the governor general of the province of Azarbaijan was no doubt the strongest among senior princes, even though it was complicated by the burdensome task of defending the northwestern frontiers against Russia. The sobering experience of defeat in the first round of the Russo-Persian wars (1805–1813) and the loss of territories in the Caucasus had already jeopardized his predominance. In subsequent years, the anxious prince tried to consolidate his position by making himself equally indispensable to Fath 'Ali Shah in Tehran, to the tsar in St. Petersburg, and to the British government in London. He began to appreciate the benefits of maintaining friendly relations with Iran's northern neighbor, although such relations did not wholly extinguish his chronic desire to recapture lost territories.
The Treaty of Gulistan (1813), which ended the first round of Russo-Persian wars, guaranteed the tsar's support for the crown prince of Iran, but it also barred the Russian sovereign from interfering in the choice of the heir apparent should a dispute develop among the princes.[27] At about the same time the treaties of 1812 and 1814 with England stipulated similar assurances. Although these provisions seemed intended to strengthen 'Abbas Mirza's hand, they also left the door open for future challenges by his brothers. Such uncertainties in the event of a dispute indicated that in the early decades of Fath 'Ali's reign the question of apparency was still not fully resolved; a free-for-all contest between the qualified princes was still to determine the future of the throne.