The Deli Sultanate refers to the many Muslim dynasties that ruled in India from 1206 to 1526. Several Turkish and Afghan dynasties ruled from Delhi: the Slave dynasty (1206-90), the Khilji dynasty (1290-1320), the Tughlaq dynasty (1320-1413), the Sayyid dynasty (1414-51), and the Lodi dynasty (1451-1526).
During the last quarter of the twelfth century, Muhammad of Ghor invaded the Indo-Gangetic plain, conquering in succession Ghazni, Multan, Sindh, Lahore, and Delhi. Qutb-ud-din Aybak, one of his generals proclaimed himself Sultan of Delhi. In the 13th century, Shams ud din Iltumish (1211 - 1236), a former slave-warrior, established a Turkic kingdom in Delhi, which enabled future sultans to push in every direction; within the next 100 years, the Delhi Sultanate extended its way east to Bengal and south to the Deccan, while the sultanate itself experienced repeated threats from the northwest and internal revolts from displeased, independent-minded nobles. The sultanate was in constant flux as five dynasties rose and fell. The Khilji dynasty, under Ala ud din (1296 - 1316), succeeded in bringing most of South India under its control for a time, although conquered areas broke away quickly. Power in Delhi was often gained by violence (nineteen of the thirty-five sultans were assassinated) and was legitimized by reward for tribal loyalty. Factional rivalries and court intrigues were as numerous as they were treacherous; territories controlled by the sultan expanded and shrank depending on his personality and fortunes.
Both the Qur'an and sharia (Islamic law) provided the basis for enforcing Islamic administration over the independent Hindu rulers, but the sultanate made only fitful progress in the beginning, when many campaigns were undertaken for plunder and temporary reduction of fortresses. The effective rule of a sultan depended largely on his ability to control the strategic places that dominated the military highways and trade routes, extract the annual land tax, and maintain personal authority over military and provincial governors. Sultan Ala-ud-Din made an attempt to reassess, systematize, and unify land revenues and urban taxes and to institute a highly centralized system of administration over his realm, but his efforts were abortive. Although agriculture in North India improved as a result of new canal construction and irrigation methods, including what came to be known as the Persian wheel, prolonged political instability and parasitic methods of tax collection brutalized the peasantry. Experts in metalwork, stonework, and textile manufacture responded to the new patronage with enthusiasm. In this period Persian language and many Persian cultural aspects became dominant in the centers of power in India.
In 1526 the Delhi Sultanate was absorbed by the emerging Mughal Empire. Mughal is the Persian word for Mongol and was generally used to refer to Central Asian nomads who claimed descent from the Mongol warriors of Genghis Khan. The foundation for empire was established around 1504 by the Timurid prince Babur, when he took control of Kabul and eastern regions of Khorasan controlling the fertile Sind region and the lower valley of the Indus River. In 1526, he defeated the last of the Delhi Sultans, Ibrahim Shah Lodi, at the First Battle of Panipat. These early military successes of the Mughals in India, carried out by an army much smaller in size than its opponents, have been attributed to their cohesion, mobility, and horse-mounted archers.
The Mughal Empire lasted from the early sixteenth to the mid-nineteenth century. At its peak (around 1700) it covered most of the Indian subcontinent and parts of what is now Afghanistan. Its population at that time has been estimated as between 100 and 150 million, over a territory of over 3 million square km. After 1720, it declined rapidly. The decline has been variously described as due to wars of succession, agrarian crises fueling local revolts, and the growth of a religious extremism by the Hindu and Sikh population. The last Emperor, whose rule was restricted to the city of Delhi, was imprisoned and exiled by the British after the War of Independence Rebellion of 1857.
The classic period of the Empire starts with the accession of Akber in 1556 and ends with the death of Aurangzeb in 1707. During this period, the Empire was marked by a strongly centralized administration connecting the different regions of India. All the significant monuments of the Mughals, their most visible legacy, date to this period.
The decline of the Mughal Empire has been studied under several different theories. Some historians such as Irfan Habib have described the decline of the Mughal Empire in terms of class struggle. Habib proposed that excessive taxation and repression of peasants created a discontented class that either rebelled itself or supported rebellions by other classes and states. On the other hand, Athar Ali proposed a theory of a "jagirdari crisis." According to this theory, the influx of a large number of new Deccan nobles into the Mughal nobility during the reign of Aurangzeb created a shortage of agricultural crown land meant to be allotted, and destroyed the crown lands altogether. The classical theory of Aurangzeb's Islamicism and Mughal decline continues to find a new life in the research of S. R. Sharma. Other theories put weight on the devious role played by the Saeed brothers in destabilizing the Mughal throne and auctioning the agricultural crown lands for revenue extraction.
The Mughal period would see a more fruitful blending of Indian, Iranian and Central Asian artistic, intellectual and literary traditions than any other in Indian history. The Mughals had taste for the fine things in life - for beautifully designed artifacts and the enjoyment and appreciation of cultural activities. The Mughals borrowed as much as they gave - both the Hindu and Muslim traditions of India were huge influences on their interpretation of culture and court style. Nevertheless, they introduced many notable changes to Indian society and culture, including centralized government which brought together many smaller kingdoms, Persian art and culture amalgamated with native Indian art and culture, started new trade routes to Arab and Turk lands, Mughali cuisine, Urdu and spoken Hindi languages were formed for common Muslims and Hindus respectively, a new style of architecture, and Landscape gardening.