Invaders not only looted India's wealth, but also disrupted social life, economic systems and educational institutions
India or Bharat was the world's top economy during the first millennia, from 1 CE to 1000 CE. However, due to Islamic invaders and later by European colonizers, India lost a significant percentage of its wealth. For better understanding, let us take a look at who looted India and how much from India.
Persian invasion to India - During the 6th century BCE to 4th century BCE, the Indus Valley was invaded by the Achaemenid Persian Empire. They captured land, which is largely modern-day Pakistan. The conquest was carried out by Cyrus the Great, the founder of the empire. Later, his son Darius the Great I further expanded the empire by invading Punjab and Sindh areas. The conquest continued with Xerxes, the son of Darius. Significant amount of wealth was captured, but proper estimates are not available.
Greek invasion, led by Alexander - This occurred in 326 BCE, when Alexander reached India and fought with King Porus. Although Alexander won, the enormous war effort prompted his army to retreat. This could have been another conquest, but the intense battle stopped Alexander's plans to enter deep into India. However, Greek invasions did not stop after Alexander. It continued with the invasion by the Seleucid army from 305 - 303 BC. Later in 180 BC, India was again invaded by Indo-Greek king Demetrius.
Huna invasion - This occurred around 5th century CE, wherein the Hunas fought with the Gupta Empire in northern India. They looted regions that are present day Rajasthan, Punjab and other central Indian areas. The Hunas were eventually defeated by next-generation Gupta kings, Yashodharman of Malwa, etc.
Muhammad bin Qasim - This began in 712 CE and marks the beginning of Islamic invasion and conquest into India. Muhammad bin Qasim represented the Umayyad Caliphate and served as an Arab military commander. His first conquest was Sindh, which is currently located in Pakistan.
Mahmud of Ghazni - This represented the invasion of India by the Turks, led by Mahmud of Ghazni. He destroyed and looted various temples including Somnath and Mathura. Mahmud of Ghazni carried out the loot repeatedly, around 17 times. The looted wealth was sent back to his homeland and used for constructing his capital in Ghazni. In just a single raid at Somnath temple, Mahmud of Ghazni looted treasures worth millions of gold dinars.
Muhammad Ghori - This invasion of India occurred in 1175 AD. He was opposed by Rajput chiefs and was defeated in 1191 CE in the First Battle of Terrain. However, Muhammad Ghori came back with a larger army in 1192 and defeated the Rajputs. It resulted in the death of Prithvi Raj Chauhan. After winning, Muhammad Ghori plundered the wealth of Delhi and Ajmer. His armies looted various palaces, temples and treasuries. However, it is difficult to estimate the total wealth looted by Muhammad Ghori.
Invasion by Mongol - This occurred during the period from 1206-1368 CE. Most notorious was Timur, who laid the foundation of the Timurid Empire. He looted immense wealth from India between 1398 to 1399. The looted wealth included jewelry, gold, silver and other treasures. The wealth looted from India enriched Timur's empire for years. Timur also massacred people.
Mughal invasion - This started in 1526 CE, led by Babur. He became a prominent ruler after defeating the Delhi Sultanate. Mughals made significant money by imposing heavy taxes on traders and farmers. While the Mughal kings became rich, the people suffered. A significant part of the loot was sent to the Islamic world.
Invasion by Nader Shah - A powerful Iranian invader, Nader Shah attacked the Mughals in Delhi in 1739. After winning the battle, Nader Shah looted Delhi and massacred the population. His loot included the Kohinoor diamond and the Peacock Throne.
European / British invasion - India became a target by multiple European powers including British, French, Dutch and Portuguese. However, most significant loot is attributed to the British colonization of India during the 18th-20th century. Significant amounts of gold and silver were moved from India to Europe. India also faced a significant drain of resources. Estimates indicate that wealth looted by the British was around £45 billion during the period from 1765 to 1938. This will be valued at around $45–$100 trillion, as per today's valuation.