From their roots as a Turkmen tribe of shepherd-warriors centered in Azerbaijan, the Qajar Dynasty would become a fully assimilated Perso-Islamic monarchy that reunified Persia and, through their modernization programs, laid the foundation for the modern nation-state now known as Iran. Following the demise of the Safavid Dynasty, various regional centers of powers emerged, including the Zand Dynasty that controlled the south. In 1779, after the death of the Zand leader, Agha Mohammed Khan, the founder of the Qajar Dynasty, set out to reunify Persia under the Qajar banner. By 1794, Agha Mohammed Khan had defeated his internal rivals and reestablished Persian sovereignty over territories in Georgia and the Caucasus previously lost to foreign powers. These territorial gains would not last long, however, as the Qajaris soon found themselves in direct conflict with the imperial aspirations of Russia and Britain. Fath Ali Shah, who rose to the throne following the assassination of Agha Mohammed in 1797, presided over a period of disastrous conflicts with Russia, which resulted in an acknowledgement of Russian sovereignty over Georgia and later the entire South Caucasus region north of the Aras River.
Historically, perhaps the most significant development that occurred under the Qajars were the modernization reforms implemented under Naser o-Din Shah, who reigned from 1848-1896. Western style methods of education and science were implement, European technologies were imported, and academics from abroad were brought in to assist in the process, effectively ushering Persian society out of the Medieval era and into the Modern. Despite his efforts, Naser o-Din Shah was unable to hault European encroachment into areas of traditional Persian influence. By the end of the 19th century, the Qajars found themselves surrounded by the powers of the Ottoman Empire to the west, Russia to the north, and the British to the east. The early 20th century ushered in a period of great social upheaval, resulting in a Consitutional Revolution that challenged the power of the monarchy and led to conflicts between the crown and the nascent parliament. The resulting chaos seriously weakened the state to the point that Britain and Russia agreed to divide Persia among themselves into spheres of influence under the Anglo-Russia Agreement of 1907. By the onset of World War I, any semblance of Persian independence was effectively over. Following a coup d’état by Reza Khan, the moribund Qajari Dynasty was formally disbanded.