The founder of the Tughlaq dynasty was Ghiyasuddin Tughlaq. Ghiyasuddin Tughlaq sent his son Juna Khan to fight against Warangal. He defeated Pratabarudra and returned with rich booty. Ghiyasuddin laid the foundation for Tughlaqabad near Delhi. Ulugh Khan was said to have treacherously killed his father and ascended the throne with the title Muhammad bin Tughlaq in 1325.
He was a very attractive character in the history of medieval India owing to his ambitious schemes and novel experiments. His enterprises and novel experiments ended in miserable failures because they were all far ahead of their time. He was very tolerant in religious matters. He maintained diplomatic relations with far off countries like Egypt, China and Iran. He also introduced many liberal and beneficial reforms. But all his reforms failed. Contemporary writers like Isami, Barani and Ibn Battutah were unable to give a correct picture about his personality. But, Muhammad bin Tughlaq was the only Delhi Sultan who had received a comprehensive literary, religious and philosophical education.
Muhammad bin Tughlaq wanted to make Devagiri his second capital so that he might be able to control South India better. In 1327 he made extensive preparations for the transfer of royal household and the ulemas and Sufis from Delhi to Devagiri, which was renamed as Daulatabad. When they resisted the Sultan enforced his orders ruthlessly and caused great hardship of the population of Delhi. The distance between these two places was more than 1500 kilometres. Many people died during the rigorous journey in the summer. After two years, the Sultan abandoned Daulatabad and asked them to return to Delhi.
In 1329-30 Muhammad bin Tughlaq introduced a token currency. There was a shortage of silver through out the world in the fourteenth century. Kublai Khan issued paper money in China. In the same manner, Muhammad bin Tughlaq issued copper coins at par with the value of the silver tanka coins. But he was not able to prevent forging the new coins. The goldsmiths began to forge the token coins on a large scale. Soon the new coins were not accepted in the markets. Finally, Muhammad bin Tughlaq stopped the circulation of token currency and promised to exchange silver coins for the copper coins. Many people exchanged the new coins but the treasury became empty. According the Barani, the heap of copper coins remained lying on roadside in Tughlaqabad.
The failure of these two experiments affected the prestige of the Sultan and enormous money was wasted. In order to overcome financial difficulties, Muhammad bin Tughlaq increased the land revenue on the farmers of Doab (land between Ganges and Yamuna rivers). It was an excessive and arbitrary step on the farmers. A severe famine was also ravaging that region at that time. It had resulted in a serious peasant revolts. They fled from the villages but Muhammad bin Tughlaq took harsh measures to capture and punish them. The revolts were crushed.
However, the Sultan realized later that adequate relief measures and the promotion of agriculture were the real solution to the problem. He launched a scheme by which takkavi loans (loans for cultivation) were given to the farmers to buy seed and to extend cultivation. A separate department for agriculture, Diwan- i- Kohi was established. Model farm under the state was created in an area of 64 square miles for which the government spent seventy lakh tankas. This experiment was further continued by Firoz Tughlaq.
The latter part of Muhammad bin Tughlaq's reign witnessed a spate of rebellions by the nobles and provincial governors. The rebellion of Hasan Shah resulted in the establishment of the Madurai Sultanate. In 1336 the Vijayanagar kingdom was founded. In 1347 Bhamini kingdom was established. The governors of Oudh, Multan and Sind revolted against the authority of Muhammad bin Tughlaq. In Gujarat Taghi rose in revolt against the Sultan who spent nearly three years in chasing him. Muhammad bin Tughlaq's health became worse and he died in 1351. According to Baduani, the Sultan was freed from his people and the people from the Sultan. According to Barani, Muhammad bin Tughlaq was a mixture of opposites. His reign marked the beginning of the process of its decline.
After the death of Muhammad-bin-Tughlaq in 1351 Firoz Tughlaq had the unique distinction of being chosen as sultan by the nobles. He appointed Khan-i-Jahan Maqbal, a Telugu Brahmin convert as wazir (prime minister). The wazir helped the Sultan in his administration and maintained the prestige of the Sultanate during this period.
After his accession Firoz had to face the problem of preventing the disintegration of the Delhi Sultanate. He tried to safeguard his authority over north India instead of reasserting his authority over the Deccan and south India. He led two expeditions to Bengal but they were not successful. Bengal became free from the control of Delhi Sultanate. Firoz led a campaign against Jajnagar (modern Orissa). He returned with rich booty acquired from the temples. He marched against Nagarkot and made its ruler to pay tributes. During this campaign the Sultan collected 1300 Sanskrit manuscripts from the Jawalamukhi temple library and got them translated into Persian. Firoz next marched against Thatta in the Sind region and crushed a rebellion there.
The reign of Firoz Tughlaq was more notable for his administration. He strictly followed the advice of the ulemas in running the administration. He pleased the nobles and assured hereditary succession to their properties. Thus the iqta system was not only revived but also it was made hereditary. As per the Islamic law he levied the taxes. Jiziya was strictly imposed on non-Muslims. He was the first Sultan to impose irrigation tax. But at the same time he dug irrigation canals and wells. The longest canal was about 200 kilometres from Sutlej to Hansi. Another canal was between Yamuna and Hissar. There were about 1200 fruit gardens in and around Delhi yielding more revenue. The special tax on 28 items was abolished by him since they were against the Islamic law. He also developed royal factories called karkhanas in which thousands of slaves were employed. About 300 new towns were built during his reign. The famous among them was Firozabad near Red Fort in Delhi, now called Firoz Shah Kotla. Old monuments like Jama Masjid and Qutb-Minar were also repaired.
A new department called Diwan-i-Khairat was created to take care of orphans and widows. Free hospitals and marriage bureaus for poor Muslims were also established. Firoz patronized scholars like Barani and Afif. As he was guided by the ulemas, he was intolerant towards Shia Muslims and Sufis. He treated Hindus as second grade citizens and imposed Jiziya. In this respect he was the precursor of Sikandar Lodi and Aurangazeb. Also he increased the number of slaves by capturing the defeated soldiers and young persons. In his regime the number of slaves had increased to one lakh eighty thousand. When Firoz died in 1388 the struggle for power between the Sultan and the nobles started once again. His successors had to face the rebellion of the slaves created by Firoz.
In the following years, the Delhi Sultanate had disintegrated further. Many provinces like Malwa and Gujarat declared their independence. The invasion of Timur in 1398 had worsened the situation. When Timur entered Delhi there was no opposition and he sacked Delhi for three days murdering thousands of people and looting enormous wealth. He withdrew from India in 1399 and his invasion in fact delivered a death blow to the Tughlaq dynasty.