In 1738-39, Nadir Shah descended upon the plains of northern India.
Nadir Shah was attracted to India by the fabulous wealth for which it was always famous. The visible weakness of the Mughal Empire made such spoliation possible.
Nadir Shah marched on to Delhi and the Emperor Muhammad Shah was taken as prisoner.
A terrible massacre of the citizens of the imperial capital was ordered by Nadir Shah as a reprisal against the killing of some of his soldiers.
The greedy invader Nadir Shah took possession of the royal treasury and other royal property, levied tribute on the leading nobles, and plundered Delhi.
Nadir Shah’s total plunder has been estimated about 70 crores of rupees. This enabled him to exempt taxation of his own Kingdom for three years.
Nadir Shah also carried away the famous Koh-i-nur diamond and the Jewelstudded Peacock Throne of Shahjahan.
Nadir Shah compelled Muhammad Shah to cede to him all the provinces of the Empire falling west of the river Indus.
Nadir Shah's Invasion inflicted immense damage on the Mughal Empire. It caused an irreparable loss of prestige and exposed the hidden weaknesses of the Empire to the Maratha Sardars and the foreign trading companies.
The invasion ruined imperial finances and adversely affected the economic life of the country. The impoverished nobles began to rack-rent and oppress the peasantry even more in an effort to recover their lost fortunes
The loss of Kabul and the areas to the west of the Indus once again opened the Empire to the threat of invasions from the North-West. A vital line of defense had disappeared.