By the beginning of the 18th century, the sedentary regions of Western Turkestan were in a state of deep political and economic crisis, with the collapse of the ruling dynasties and central governments in the Ozbek khanates, the revival of tribal powers, and disruption.
Economic life, increasing involvement of steppe nomads in the affairs of sedentary nations (Kazakhs and Turkmens of Bukhara).Khorezm). #Ubaidullah Khan (II) (1702-1711), son and successor of Subhan-Quli Khan in Bukhara, tried to reverse and limit this process. The power of the tribal chiefs, perhaps with the support of the townspeople, but his misguided economic policy led to a rebellion in the city.
Bukhara in 1708, which ended in a settlement between the government and the rebels. Khan became a victim of Osbek's conspiracy the Amir was assassinated and the central government lost all its powers and the kingdom under his successor, Abul-Faiz Khan (1711-1747). Practically dispersed into several tribal chiefdoms, the largest of which were the Mings of Ferghana, the Yus of Yura-Tub, and the Hisar. Kenegas of Sharizabs. Balkh eventually broke away from the Khanate, and the Ozbek emirs who ruled it invited some of the Ashtarkhanids who lived in Khorasan as puppet khans. By the end of the 17th century, Fergana had been separated. Wars between various rival clans affected much of the central region of the Mavarannahar, and were ravaged for seven years by the Kazakhs who fled down the Syr-Darya. From Invasion Jungars (see below). Urban dwellers and villagers began to flee from the areas most seriously affected by these disturbances, so that Samarkand was completely abandoned (cf. Map 41), and Bukhara was inhabited only in two urban quarters.
By 1730 When the Kazakhs left Mavarannahar, the power of the central government in Bukhara was limited to a few districts closest to the capital. In Bukhara itself power was gradually concentrated in the hands of Muhammad Hakim b., the head of the Khan's ataliq (chief adviser). Manganite tribe.

A similar political and economic decline took place in Khorezm. The #Arabshahid dynasty was extinguished between 1694 and 1727, and the northern, predominantly nomadic, half of the country, known as Aral, seceded and for more than a century remained most of the time not only independent from, but also at war with, Khiva. From the end of #Arabshahid rule there was a marked increase in the Turkmen presence in Khorezm, and the
Turkmen tribes of Salor, Chowdur, and Youth took part in the feuds among different Uzbek factions. The increasing role of the Turkmens in Khorezm coincided with the expansion of the Turkmen tribes into northern Khorasan, made possible by the fall of the Safavids in Iran. In the 1710s and 1730s the khans of Khiva were also raiding Khorasan.

Safavid Iran in the early 18th century experienced a political and economic crisis similar to that of the Central Asian khanates. But the decline and fall of the Safavids resulted first in the rise of Nadir Shah Afshar (regent from 1732, shah from 1736).
A ruthless ruler and an outstanding general, who suppressed rebellions in the provinces, defeated the Ottomans, subdued the Afghan tribes, repelled the Turkmens from the northern regions of Khorasan, and invaded and sacked the Mughal capital, Delhi. In 1736-37 his son, Riza-Quli Mirza, occupied Balkh and its entire province, and later in 1737, while Nadir Shah was at Qandahar, he launched an attack on Bukhara and besieged Abu’l-Fayz Khan in Qureshi, but was recalled by Nadir Shah.
The latter invaded Bukhara himself in 1740. One part of his army crossed the Amu-Darya at Kelif, while the main army went along the left bank and crossed at Charjuy. Here a number of Uzbek amirs came to his camp and offered their submission; then Nadir Shah marched on Bukhara, set up his camp in a suburb of the city and received there the submission of Abu’l-Fayz Khan.Bukhara was spared a Persian occupation, but the khanate had to supply to the Persian army a large quantity of grain and fodder as well as 10,000 horsemen, under Muhammad Rahim Biy, the son of Muhammad Hakim Atalïq. From Bukhara Nadir Shah marched along the left bank of the Amu-Darya on Khiva, defeated the Khorezmian army in two battles and besieged the khan in the city of Khanqah. After seven days’ siege Ilbars Khan surrendered and was executed together with twenty of his amirs, and Khiva surrendered several days later. Nadir Shah set free all the slaves in Khorezm (Persians, Russians, Qalmaqs) and had Khorezm provide the Persian army with grain and 4,000 horsemen. Nadir Shah left Khorezm after installing as khan a relative of the Bukharan Ashtarkhanids. Later on Nadir Shah did not interfere in the internal affairs of either khanate (beyond sending troops to Khorezm to suppress a Turkmen rebellion in 1745). Both khanates were now actually ruled by the chieftains of the Manghir tribe of the Uzbeks, who enjoyed Nadir’s support.