The Tughlaqs [1320 AD - 1412 AD]
The Tughlaqs also wished to rule the whole of India. Ghyasuddin's (1320 AD - 1325 AD) campaign to Warrangal, Orissa and Bengal were directed towards this end. He built the city Tughlaqabad near Delhi. By 1324 AD, the territories of the Delhi sultanate reached upto Madurai. However, his economic policy was not consistent with his political ambitions. As the Iqta holders were permitted their earlier perquisites, power gradually slipped back into the hands of nobles.
Muhammad-Bin-Tughlaq (1325 AD - 1351 AD)
succeeded his father and was referred to as an ill-starred idealist,
whose experiments generally ended in failure. He extended the kingdom beyond
India, into Central Asia.
To meet the the expenses of the large army Muhammad increased the tax but the peasants refused and rebelled. Though the rebellion was suppressed, the taxation policy had to be revised. He decided to issue token coins in brass and copper which had the same value as silver coins. But due to the absence of a central mint, people began to forge the new coins, and the token coins had to be discontinued. He also decided to move his capital from Delhi to Deogir (Daulatabad), in order to control the Deccan and extend the empire into the south. The plan ended in failure because of discontent amongst those who had been forced to move to Deogir and Muhammad also found that he could not keep a watch on the northern frontier.
In 1334 bubonic plague wiped out more than half his army, and the army ceased to be effective. Due to this, in 1334 the Pandyan kingdom (Madurai) rejected the authority of the sultanate and this was followed by Warangal. In 1336 the Vijayanagara empire and in 1337 the Bahamani kingdom were founded. They built magnificent capitals and cities with many splendid buildings, promoted arts and also provided law and order and the development of commerce and handicrafts. Thus while the forces of disintegration gradually triumphed in north India, south India and the Deccan had a long spell of stable government.
Firoz Shah Tughlaq (1351 AD - 1388 AD) succeeded Muhammad. Having become sultan with the support of the nobles and the theologians, he had to appease them. His death was followed by civil war among his descendants.
The sultanate became weak and in 1398, the Mongols, under the leadership of Timur (Tamerlane), mercilessly sacked and plundered Delhi. Timur returned to central Asia leaving his nominee to rule in the Punjab.