The new ruler quickly abolished most of Amanullah's reforms, but despite his efforts to rebuild an army that had just been engaged in suppressing a rebellion, the forces remained weak while the religious and tribal leaders grew strong. In 1930, there were uprisings by the Shinwari Pushtuns as well as by another Tajik leader. The same year, a Soviet force crossed the border in pursuit of an Uzbek leader whose forces had been harassing the Soviets from his sanctuary in Afghanistan. He was driven back to the Soviet side by the Afghan army in April 1930, and by the end of 1931 most uprisings had been subdued.

Nadir Shah named a ten-member cabinet, consisting mostly of members of his family, and in September 1930 he called into session a loya jirgah of 286 which confirmed his accession to the throne. In 1931 the king promulgated a new constitution. Despite its appearance as a constitutional monarchy, the document officially instituted a royal oligarchy, and popular participation was merely an illusion.

Although Nadir Shah placated religious factions with a constitutional emphasis on orthodox denominational principles, he also took steps to modernize Afghanistan in material ways, although far less obtrusively than his cousin Amanullah. He improved road construction, especially the Great North Road through the Hindu Kush, and methods of communication. He forged commercial links with the same foreign powers that Amanullah had established diplomatic relations with in the 1920s, and, under the leadership of several prominent entrepreneurs, he initiated a banking system and long-range economic planning. Although his efforts to improve the army did not bear fruit immediately, by the time of his death in 1933 Nadir Shah had created a 40,000-strong force from almost no national army at all. It is notable that Afghanistan's regeneration was carried out with no external assistance whatsoever.

Nadir Shah's brief four year reign ended violently, but he nevertheless accomplished a feat of which his great-great-uncle, Dost Mohammad, would have been proud: he reunited a fragmented Afghanistan. Nadir Shah was assassinated in 1933 by a young man whose family had been feuding with the king since his accession to power.

Data as of 1997