and mandating that taxes be paid in the well-regulated silver currency, caused peasants and artisans to enter larger markets. The relative peace maintained by the empire during much of the 17th century was a factor in India's economic expansion, resulting in greater patronage of painting, literary forms, textiles, and architecture. The Mughal Empire was the world's largest economy in the 17th century, larger than Qing China and Western Europe, with Mughal India producing about a quarter of the world's economic and industrial output. In the 18th century, Mughal power had become severely limited. By the mid-18th century, the Marathas had routed Mughal armies and invaded several Mughal provinces from the Punjab to Bengal. By this time, the dominant economic powers in the Indian subcontinent were Bengal Subah under the Nawabs of Bengal and the South Indian Kingdom of Mysore under Hyder Ali and Tipu Sultan, before the former was devastated by the Maratha invasions of Bengal, leading to the economy of the Kingdom of Mysore overtaking Bengal. The British East India Company conquered Bengal in 1757 and then Mysore in the late 18th century. The last Mughal emperor, Bahadur Shah II, had authority over only the city of Old Delhi (Shahjahanabad), before he was exiled to Burma by the British Raj after the Indian Rebellion of 1857. Role in the Indian independence movement The contribution of Muslim revolutionaries, poets and writers is documented in the history of India's struggle for independence. Titumir raised a revolt against the British Raj. Abul Kalam Azad, Hakim Ajmal Khan and Rafi Ahmed Kidwai are other Muslims who engaged in this endeavour. Ashfaqulla Khan of Shahjahanpur conspired to loot the British treasury at Kakori(Lucknow) (See Kakori conspiracy). Khan Abdul Gaffar Khan (popularly known as "Frontier Gandhi") was a noted nationalist who spent 45 of his 95 years of life in jail; Barakatullah of Bhopal was one of the founders of the Ghadar Party, which created a network of anti-British organisations; Syed Rahmat Shah of the Ghadar Party worked as an underground revolutionary in France and was hanged for his part in the unsuccessful Ghadar Mutiny in 1915; Ali Ahmad Siddiqui of Faizabad (UP) planned the Indian Mutiny in Malaya and Burma, along with Syed Mujtaba Hussain of Jaunpur, and was hanged in 1917; Vakkom Abdul Khadir of Kerala participated in the "Quit India" struggle in 1942 and was hanged; Umar Subhani, an industrialist and millionaire